I'd suggest Abba Seraphim's adresses 'Two Families of Orthodoxy: An Ecumenical perspective' and 'Towards a common Christology.' Both highlight some of the issues which have occurred.
An interesting take on the subject is 'Chalcedon revisited' from Ancient Faith Radio which looks into the historical and Christological debate from the Byzantine side: Chalcedon Revisited
Either way, this Christology has not been as much of an issue in the past, such examples as 1861 and other attempted reunifications have shown that the Miaphysite Christology is Orthodox (As confirmed by the join commission 19 years ago) but those that wish to oppose recommunion will do their best to prevent it, claiming 'ambiguity' or that 1550 or so years is rushing things.
- Interesting article on the subject.
Beyond Dialogue: The Quest for Eastern and Oriental Orthodox Unity Today
John H Erickson, Dean
Symposium on 1700th Anniversary of Christian Armenia
October 27-28, 2000
Henry Chadwick, distinguished church historian and veteran observer of the ecumenical scene, is fond of remarking that the chief reason for Christian division today is division itself. Whatever may have been the issues initially leading to division, a division once established very quickly takes on a life of its own, as each side tries to justify its own role in the division. Differences that would not in themselves have been church-dividing are invested with new meaning, to the point of becoming symbols of division rather than examples of legitimate diversity. Signs of particular divine favor are discovered on each side, whether in supernatural portents or in the steadfastness of new confessors and martyrs. Competing ecclesial structures are erected. Anathemas are hurled. And even if the issues that led to the division are eventually resolved, the division itself - buttressed in these many ways - remains.
Certainly these generalizations hold true if we look at the long history of relations between the Eastern, or Chalcedonian, Orthodox Churches and the Oriental, or Non-Chalcedonian, Orthodox Churches. As these commonly-used designations suggest, both families of churches regard themselves as orthodox, as “right-believing,” or (more accurately) as “right worshipping.” But they have differed on their position with regard to the Council of Chalcedon (451 A.D.) and the definition on Christological dogma made at that council. Thus their long and often painful division goes back over 1500 years. In recent decades relations have begun to improve, yet developments have been both encouraging and frustrating. Encouraging - because theological dialogue, first informal in the 1960s, then formal in the 1980s and 1990s, has led to the conclusion that the Christological issues that initially prompted the division of these churches have been resolved, so that continued division can no longer be justified on dogmatic grounds. Frustrating - because the division does continue. At this point the reason for the division of our churches seems to be division itself. A closer review of relations between our churches in the last decades of the twentieth century may place in sharper relief both how far they have come in their quest for unity and also how many divisive and potentially divisive issues remain.
In this year in which we commemorate the 1700th anniversary of Armenian Christianity, it may be useful to begin our review with another anniversary year, 1951, the 1500th anniversary of the Council of Chalcedon. In a letter commemorating that anniversary, Patriarch Athenagoras of Constantinople quoted with approval St. John of Damascus, who in the eighth century observed that those who do not accept the terminology of Chalcedon were “nevertheless Orthodox in all things,” and he called for theological dialogue with the Non-Chalcedonian churches. The openness of Patriarch Athenagoras stands in contrast to the way in which Chalcedon was presented in popular literature of the period. On the Chalcedonian side, Chalcedon then as now was numbered as the fourth of the seven ecumenical councils; and just as the other ecumenical councils, it was remembered chiefly in terms of the heresy condemned. Just as I Nicaea had condemned the Arian heresy, I Constantinople the Macedonian heresy, and Ephesus the Nestorian heresy, so also Chalcedon had condemned the monophysite heresy. Those whom the Eastern Orthodox (or for that matter Western Christians) today refer to as Oriental Orthodox or Non-Chalcedonians were most often called monophysites in popular books of the period. The genesis of this heresy and its condemnation at Chalcedon were presented more or less like this: The Council of Ephesus (431 A.D.) quite rightly had condemned Nestorius for emphasizing Christ’s humanity to the point of separating Him into two persons; by contrast Nestorius’ chief opponent, Cyril of Alexandria, emphasized Christ’s divine nature, and followers such as Eutyches quickly enough carried this to an extreme, to the point of denying Christ’s human nature; so Chalcedon, basing itself on the carefully balanced Christology of the Tome of Pope Leo of Rome, quite rightly condemned this monophysite heresy, this heresy which held that Christ had but one nature, viz. the divine.
This, of course, is the stereotype that was widespread among the Eastern Orthodox circa 1951. No doubt comparable stereotypes existed among the Oriental Orthodox. For most Orthodox, however, whether Eastern or Oriental, the climate of opinion has changed considerably since 1951. Why?
(1) First of all, we must acknowledge the contribution of the modern ecumenical movement. Both the Eastern Orthodox and the Oriental Orthodox Churches have criticized certain developments within the ecumenical movement, and quite rightly. At the same time, both have benefited from the ecumenical movement in diverse ways. The very dialogue which has brought these churches so close to the point of unity and full communion is, in many respects, a product of the ecumenical movement and, more specifically, of the close contacts and resulting friendships which this movement has made possible. Back in the early 1960s, two then-young staff members of the World Council of Churches, Nikos Nissiotis and Paul Verghese - later Mar Paulos Gregorios - of the Malankara Syrian Orthodox Church, sensed the fundamental unity of the Eastern and Oriental churches. They succeeded in winning over their respective church authorities, and in turn - at first in conjunction with meetings of the Faith and Order Commission of the World Council of Churches - a series of informal consultations began (1964-71). In an atmosphere of mutual respect, relatively free from the cultural and political pressures that had doomed earlier attempts at reunion, leading theologians from both sides  were able to address the subject of Christology from a fresh perspective, concentrating not on what divides (as in older polemical literature) but rather on what unites (in this case, our common father from the early Church, St. Cyril of Alexandria, and his formulation “one incarnate nature of God the Word”).
Already the joint statement issued by the first of these informal consultations (Aarhus 1964) could declare: “We recognize in each other the one Orthodox faith of the church. Fifteen centuries of alienation have not led us astray from the faith of our fathers.... On the essence of the Christological dogma we found ourselves in full agreement. Through the different terminologies used by each side, we found the same truth expressed.” The second informal consultation (Bristol 1967) extended agreement to include virtually every hitherto-disputed aspect of Christology: “Some of us affirm two natures, wills and energies hypostatically united in the one Lord Jesus Christ. Some of us affirm one united divine-human nature, will and energy in the same Christ. But both sides speak of a union without confusion, without change, without division, without separation. These four adverbs” - which of course lie at the heart of the Chalcedonian definition - “belong to our common tradition. Both affirm the dynamic permanence of the Godhead and the Manhood, with all their natural properties and faculties, in the one Christ.” 
Building on the work of these and subsequent informal consultations, an official Joint Commission for Theological Dialogue Between the Orthodox Church and the Oriental Orthodox Churches began to meet in the 1980s. In its agreed statements on Christology, the Commission repeatedly and unequivocally affirmed the churches’ full agreement on the substance of the faith, notwithstanding differences in terminology. “In the light of our four unofficial consultations (1964, 1967, 1970, 1971) and our three official meetings which followed (1985, 1989, 1990), we have understood that both families have loyally maintained the authentic Orthodox Christological doctrine, and the unbroken continuity of the apostolic tradition, though they may have used Christological terms in different ways” (Chambesy 1993). Indeed, as the documents of the dialogue point out, “Our mutual agreement is not limited to Christology, but encompasses the whole faith of the one undivided Church of the early centuries” (Anba Bishoy 1980), including, for example, the veneration of icons. 
(2) While the modern ecumenical movement has contributed significantly to the progress in relations between our churches, we must acknowledge an even greater debt to modern historical scholarship. During the twentieth century, our churches began to engage not only in synchronous dialogue - dialogue with each other and with other churches involved in the ecumenical movement - but also in diachronous dialogue - dialogue with their own past. They discovered, among other things, that their popular presentations of the period of church history in question were gross oversimplifications. After Chalcedon, Christological positions whether among those accepting the council or those rejecting it were much more varied and fluid than popular presentations suggested, making it difficult any longer to view one “side” as purely orthodox or the other as purely heretical.
Among those rejecting Chalcedon, there were indeed some who put forward positions that quite properly could be described as monophysite, most notably Julian of Halicarnassus, who asserted that Christ’s body was by nature incorruptible from the moment of the union, even before the resurrection, so that “even though Christ wept over Lazarus, it was his incorruptible and divine tear that raised him from the dead.” But as modern specialists beginning with Lebon demonstrated conclusively, mainstream “monophysites” like Severus of Antioch simply sought to continue the mia physis Christology of St. Cyril of Alexandria.  They spoke of “one incarnate nature of God the Word,” but this did not mean that they denied the fullness of Christ’s humanity. In fact, much of their energy was spent in combatting the apthartodocetism of Julian of Halicarnassus and others like him, who compromised the fullness of Christ’s humanity by arguing that it was essentially different from our own. 
At the same time that Non-Chalcedonian “monophysitism” was being reassessed, Chalcedonian diphysitism was also being reassessed. Reacting again the older and characteristically Western approach which saw ancient church history and dogmatic development as culminating and indeed ending with Chalcedon, scholars like Fr. John Meyendorff called attention to developments after Chalcedon and indeed to neglected aspects of Chalcedon itself.  As Fr. Meyendorff often emphasized, at Chalcedon it was not just the Tome of Pope Leo of Rome that was the touchstone of orthodoxy. Whenever a difficult moment arose in the proceedings, the witness of Cyril, not just of Leo, was invoked. In addition, as Meyendorff and other scholars pointed out, Chalcedon itself left a number of issues unresolved, both in Christology and in the inseparable area of soteriology. Many - indeed perhaps the majority - of those who rejected Chalcedon did so on the grounds that it could be interpreted in a Nestorian way and that it had rehabilitated certain Nestorian sympathizers - personages like Theodoret of Cyrus, who with some justice have been labeled crypto-Nestorian. This possibility was eliminated only after yet another council, the fifth ecumenical council by Eastern Orthodox reckoning, in Constantinople in 553, during the reign of Emperor Justinian. This council once again emphasized the authority of St. Cyril, condemned the suspect Nestorian sympathizers, and fully incorporated into its definition the “theopaschite” formulations which those rejecting Chalcedon had long regarded as essential for orthodoxy. The hymn “Only-begotten Son,” generally ascribed to Justinian and sung each time the Divine Liturgy is celebrated, testifies to the continuing importance of this council’s understanding of Christology within the Byzantine tradition.
Only-begotten Son and Word of God: Thou art immortal,
yet for our salvation Thou didst deign to be incarnate
of the holy Theotokos and ever-virgin Mary,
and without change Thou didst become man and wast crucified, O Christ our God,
trampling down death by death;
Thou art one of the Holy Trinity,
glorified together with the Father and the Holy Spirit:
After 553, there would be no thought of rejecting or simply ignoring Chalcedon within the Byzantine imperial church, but it was also clear that Chalcedon could be interpreted only in the light of the Christology of St. Cyril of Alexandria and, behind that, the soteriology of St. Cyril. In short, Chalcedon, the fourth of the councils regarded as ecumenical in the Eastern Orthodox Church, does not stand alone. It must be read in the light of the fifth and subsequent councils.
The modern ecumenical movement and modern historical scholarship have indeed helped bring our churches closer. They are now able to view both each other and their own histories in a new perspective. But we should not conclude from this that the present rapprochement is simply the result of modern relativism or the “pan-heresy of ecumenism,” as some self-styled traditionalists might charge. Even during the long centuries of division there were some on both sides who recognized that differences between the churches’ preferred Christological formulations were essentially verbal rather than substantive. And during those centuries there also were efforts to reach agreement and to restore communion. These early efforts are instructive and merit closer examination. They illustrate what both sides - at the time at least - regarded as the proper basis for reunion.
Attention already has been drawn to Emperor Justinian’s efforts in the sixth century to address the legitimate concerns of those who did not accept Chalcedon. The council which he summoned did not in fact achieve its goal of unity. By that point both sides had begun to erect parallel, competing hierarchies, and ethnic, national and political issues were further aggravating what had begun as a theological dispute. The chief reason for division was becoming division itself. Yet efforts at reunion continued - and indeed intensified - under Justinian’s successor, Justin II, who issued what has been called “a manifesto of Neo-Chalcedonian theology.” Addressing all his Christian subjects, he affirmed that orthodox Christology can be expressed both in Cyrillian terms (“one incarnate nature of God the Word”) or in Chalcedonian terms (“the difference of natures is not annulled by the union...”); and he called on all parties to unite on the basis of orthodoxia, avoiding “unnecessary disputes about persons or words, since the words [used on either side] lead to one true belief and understanding.” 
One problem, of course, is that emperors of this and every age tend to become impatient when their initiatives are not immediately crowned with success. In Christian antiquity imperially sponsored dialogue too often alternated with imperially sponsored persecution of dissidents. No doubt some churchmen were happy to go along with the persecutions, just as they went along with the dialogues. But there also were those who rejected force. One such was John the Faster, a sixth-century patriarch of Constantinople. “What did the dissidents do or say that deserves persecutions?” he asked. “If pagans have been justified and amnestied, how can I persecute Christians who are blameless in their Christianity and, so it seems to me, have more faith than we?” Another noteworthy figure is John the Merciful, Chalcedonian patriarch of Alexandria, who is honored as a saint by both sides because of his even-handed charity.
During this early period there were also important developments in how each side viewed the ecclesial status of the other. In the wake of Chalcedon, some self-proclaimed champions of akribeia, or “strictness,” on both sides tried to ransack the archives of the churches to expunge the names of long-dead “heretics” and insisted on the rechrismation and reordination of those “repenting” of their former adherence. This approach, however, was vigorously resisted and ultimately defeated by moderate churchmen on both sides, who explored the proper limits of oikonomia, or “prudent pastoral management.” For example, Severus of Antioch, leading Non-Chalcedonian theologian of his age, railed against what he called “the heresy of the self-appointed reanointers,” i.e., those of his fellow Non-Chalcedonians who advocated rechrismation of Chalcedonians. On the Chalcedonian side too, we can see an analogous development in canon 95 of the Synod in Trullo, a synod which for the Chalcedonian Orthodox possesses ecumenical authority: Those coming over from among the Non-Chalcedonians are to be received simply by profession of faith, not by anointing with chrism or, a fortiori, by rebaptism.
While much of this discussion of oikonomia and its limits proceeded case by case, there was at least one attempt at a systematic presentation, a special treatise on the subject by the seventh-century Chalcedonian patriarch of Alexandria Eulogius. His work expresses what I take to be the accepted position of Chalcedonians and Non-Chalcedonians like: (a) By oikonomia a temporary concession can be made in matters of practice to avoid irremediably damaging the peace of the Church (e.g., Paul’s circumcision of Timothy); (b) by oikonomia differences in theological terminology can be tolerated indefinitely; (c) by oikonomia technical barriers to communion - an occasional heretic’s name in the diptychs and other vestiges of past error - can simply be ignored. But in no case may present purity of faith be compromised.
The proper basis for unity is orthodoxia, even if this is expressed in different Christological formulas. This was the conviction of leading figures on both sides in antiquity. This also was the conviction of the theologians who participated in the informal consultations between the churches in the 1960s and 1970s. This also forms the basis for the agreed statements issued subsequently by the official Joint Commission for Dialogue. But as is pointed out so often, orthodoxia involves not only right belief but also right worship, and in antiquity and continuing in the Middle Ages many differences in worship that would not in themselves have been church-dividing came to be invested with new meaning, becoming symbols of division.
Particularly instructive are the ways in which certain distinctive Armenian liturgical practices, such as the use of azymes (unleavened bread) and a chalice unmixed with water in the eucharist, come to be linked to Christological doctrine. The origins of these practices are unknown, but they certainly antedate any division of the churches. By late sixth century, however, they were becoming symbols of Armenian identity vis-a-vis the Greeks, who used leavened bread and wine mixed with warm water in the eucharist. Refusing an invitation from Emperor Maurice to come to Constantinople to discuss reunion, Catholicos Movses II in 591 declared: “I will not cross the River Azat nor will I eat the baked bread of the Greeks or drink their hot water.”  By the late seventh century these distinctive liturgical practices, already symbols of national identity, have become even more potent symbols of Christological doctrine. Reflecting the aphthartodocetism of Julian of Halicarnassus, which was then in the ascendency in the Armenian Church, Catholicos Sahak III (d. 703) writes: “Now we profess the body of Christ [to be] incorrupt and all-powerful always and constantly from [the moment of] the union of the Logos. This is why we take azymes [unleavened bread] for the bread of holiness with which we offer the salvific sacrifice, which signifies incorruptibility.”  Then, after a barrage of typological and moral arguments supporting the use of unleavened bread, Sahak goes on in like manner to associate the unmixed chalice, free from the adulteration of added water, with the incorruptible blood of Christ. The Byzantine Church quickly enough responded in kind. The Synod in Trullo (691-92) almost certainly had Sahak’s treatise in mind when it decreed that any bishop or presbyter who does not mix water with the wine in the eucharist is to be deposed, on the grounds that he thus “proclaims the mystery incompletely and tampers with tradition” (canon 32).  Very possibly Trullo also had Armenian liturgical practice in mind when it decreed “Let no man eat the unleavened bread of the Jews...” (canon 11). In any case, in subsequent polemical literature the issue of the bread and wine of the eucharist figures prominently, frequently to the exclusion of deeper theological reflection. Thus, despite their common rejection of Chalcedon and the generally Severan orientation of their shared Christology, the Armenian and Syrian churches in the Middle Ages sometimes attacked each other precisely because of such liturgical differences. So also, as schism yawned between the Byzantine and Latin churches in the eleventh century, Byzantine polemicists transferred their anti-azyme arguments from the Armenians to the Latins, notwithstanding the latters’ manifestly Chalcedonian Christology. Use of leavened bread and mingled wine, or conversely of unleavened bread and pure wine, immediately marked a community as either heretic or orthodox, no matter what Christological doctrine the community in question actually held!
Other liturgical practices became equally divisive. Consider, for example, the Trisagion: “Holy [is] God! Holy [and] mighty! Holy [and] immortal! Have mercy on us!” The origins of this troparion are disputed, Non-Chalcedonians claiming an Antiochian provenance and Chalcedonians attributing it to a heavenly vision when earthquakes were threatening Constantinople in 438-39. Even more disputed its interpretation. To whom is the troparion addressed? In its original form, it may have been addressed to Christ. This, in any case, is how the Non-Chalcedonian Patriarch Peter the Fuller of Antioch understood the troparion when he interpolated the theopaschite clause “who was crucified for us” into it sometime between 468 and 470, i.e., at a time when many Chalcedonians regarded any theopaschite formula with deep suspicion. Quickly enough the Trisagion became yet another bone of contention. Among Non-Chalcedonians, Catholicos Sahak III went so far as to trace the origins of the Trisagion, interpolation and all, to St. Ignatius of Antioch at the end of the first century. In response to his claims, the Synod in Trullo (691-92) condemned the interpolation “as being foreign to true piety”; and by the time of the earliest Byzantine commentary on the Divine Liturgy, that of Patriarch Germanos I in the early eighth century, the troparion was being interpreted as addressed to the three persons of the Trinity, “Holy God” referring to the Father, “Holy Mighty” to the Son, and “Holy Immortal” to the Holy Spirit. 
One final example illustrates particularly vividly the ease with which a minor liturgical difference can be transformed into a symbol of division. In the Coptic, Syrian and Armenian liturgical traditions, a week of strict fasting - variously called the Fast of Heraclius, the Fast of Ninevah or the Forefast (Arachavorats) - preceeds the “Forty-Day” Great Fast of Lent. The same week in the Byzantine tradition calls only for abstinence from meat, not from dairy products. The historical development of the fasting practices of these various liturgical traditions is complex, but the differences between them were not the result of any dogmatic differences.  Yet in the context of church division, these differences came to be given a polemical explanation. Here is the rubric given in the Byzantine Triodion for Cheesefare Sunday, which introduces the week in question: “During this week the accursed Armenians fast from eggs and cheese, but we, to refute their damnable heresy, do eat both eggs and cheese for the entire week.” What one side does is enough to prompt the other to do the opposite! We see here the tragic way in which our sense of ecclesial identity has, in the context of division, been formed by opposition rather than by reference to a common faith. The characteristics by which we identify ourselves and our churches as “orthodox” all too often have been simply those extrinsic elements which make us different from others.
Must differences of worship, once invested - however artificially - with dogmatic significance, continue to divide? In the course of the Middle Ages, a few conciliatory voices could be heard. Worthy of special mention is St. Nersess the Graceful, who in the twelfth century entered into some very promising discussions with the Byzantine didaskalos Theorianos, head of the patriarchal school and ambassador of Emperor Manuel Comnenos. St. Nersess agreed, first of all, that there was indeed unity of faith, Chalcedon notwithstanding. He writes: “I find nothing in the horos [of Chalcedon] against the Orthodox faith, and I am astonished that those before us opposed it so strenously.” He also is able to place an irenic interpretation on the liturgical diversity that distinguished the churches. For example, he observes concerning the Trisagion: “...whether one says [it] to the Holy Trinity, as you do, or to the Son alone, as we do, both are pleasing to God when they are said without contention.” Unfortunately, initiatives towards reunion in St. Nersess’ day were not carried through. The vartabeds of eastern Armenia were slow to respond. The “guardians of Orthodoxy” in Constantinople were less than enthusiastic about the emperor’s ecumenical initiatives whether towards the Armenians or towards the Latins. Perhaps more importantly, with the Battle of Myriocephalon (1176) the last remnants of Byzantine hegemony in eastern Anatolia were swept away, eliminating whatever political advantages either side might have gained by reunion.
Are current efforts to restore unity any more likely to succeed than those of the twelfth century? Certainly the modern ecumenical movement has provided a more auspicious “political” climate than that of the twelfth century, and modern scholarship has provided a clearer, more dispassionate understanding of many of the issues which have divided our churches in the past. Reflecting some of the progress that has been made in discussion of liturgical differences, the Joint Commission’s subcommittees on liturgical and pastoral issues, meeting in Damascus in February 1998, agreed - among other things - “that the Orthodox Church and the Oriental Orthodox Churches basically maintain the old liturgical traditions in their local liturgical types, which co-existed in the undivided Church”; and they also declared
that liturgical issues have to be theologically clarified to indicate that they are in agreement with our common Christological Statements. For example, the expression “who was crucified for us” in the Trisagion hymn can be properly understood only in a Christological interpretation, while the hymn without this phrase can be understood both in Trinitarian and Christological senses. In the same spirit, the use of unleavened bread and unmixed wine by the Armenian Orthodox Church in the eucharist can be explained without any implications for the Christological consensus. 
But one can sense that, in the course of the last decade, the impulse towards reunion of the churches has slowed. Articles published in the late 1980s and early 1990s, soon after the Joint Commission issued its agreed statements on Christology, could speak optimistically of “recent strides toward reunion” and “last steps to unity.”  Since then, however, progress has slowed considerably. Opposition to reunion on the basis of the agreed statements of the Joint Commission has been mounting in Greece, Russia, Jerusalem and, on the Non-Chalcedonian side, Ethiopia. An unsigned article in a “traditionalist” Orthodox periodical, reflecting this changing tide of opinion, bears the title: “Patriarch Bartholomew Attempts to Strong-Arm the Church into Union with the Monophysites.”  Particularly strident, and certainly more influential, has been the 1995 “Memorandum of the Sacred Community of the Holy Mountain [Mount Athos] Concerning the Dialogue between the Orthodox Churches and the Anti-Chalcedonian Churches.”  Many more examples could be given. This opposition to the work of the Joint Commission does not appear to be based on Christological concerns. The Athonite memorandum, for example, refers to the actual substance of Christology only twice, and even then it fails to explore the contents of the “monophysite heresy.”  Objections coming from both sides have focused rather on liturgico-canonical issues, and more specifically on the anathemas which the churches hurled against each other during their many centuries of division. According to the 1990 agreed statement of the Joint Commission, “Both families agree that all the anathemas and condemnations of the past which now divide us should be lifted by the Churches in order that the last obstacle to the full unity and communion of our two families can be removed by the grace and power of God. Both families agree that the lifting of anthemas and condemnations will be consummated on the basis that the Councils and fathers previously anathematized or condemned are not heretical.” (para. 10) But so far this has not been done. Instead, in “traditionalist” quarters on both sides, the same kinds of questions have arisen: How can we lift these anathemas without betraying our holy fathers who imposed them in the first place? How can we enter into communion with those who honor as saints precisely those whom our holy fathers in the past anathematized as heretics?
One can read statements from both Oriental and Eastern Orthodox arguing precisely this. For example, according to a popular presentation of the position of the Ethiopian Orthodox Tawahido Church:
...to lift the anathemas imposed in the past upon those Chalcedonian Fathers and to accept them as saints would dishonor those Oriental Orthodox Church Fathers who condemned the Chalcedonians.... Since these anathemas have been observed for about 1500 years by our Holy Fathers as inscribed in our liturgical texts and hymnody, they shall not be lifted. 
Much the same attitude can be seen in the memorandum from the monks of Mount Athos, which vigorously objects to “purging the liturgical books of texts which refer to the Anti-Chalcedonians as heretical.” As the memorandum continues:
The sacred services of many confessors of the Faith, of many righteous Fathers, and especially the Holy Fathers of the Fourth Council in Chalcedon will be mutilated.... We ask: Are all the texts referred to above simply ornamental elements in Orthodox hymnology so that they can be painlessly and harmlessly removed, or are they basic elements of Orthodoxy, whose removal will cause the eradication of what we understand as Orthodoxy.
The memorandum from Mount Athos also rejects that line of thinking which “considers that the anathemas were laid upon the heretics by the Ecumenical Councils in a spirit lacking love, while today, since love now exists, union can be accomplished.” “Such a way of thinking,” the memorandum states, “directs a profound blasphemy against the Holy Spirit, through Whose inspiration these decisions were made, and against the sacred memory of the Holy Fathers, whom the Churchs calls God-bearers, Mouths of the Word, and Harps of the Spirit....”
Practically inseparable from the question of anathemas is the question of the meaning and authority of ecumenical councils. The Oriental Orthodox regard three councils as ecumenical, the Eastern Orthodox, seven. It was in councils four through seven that Oriental fathers like Dioscorus of Alexandria and Severus of Antioch were condemned; and it was in these councils that Leo of Rome, condemned as crypto-Nestorian by the Orientals, was hailed as a pillar of right belief. According to the Joint Commission for Dialogue, a sufficient basis for reconciliation is the fact that both families of churches confess the faith of all seven of the councils recognized as ecumenical by the Chalcedonians, even though they do not accord the same ecumenical authority to all these councils. But is this sufficient? According to some Eastern Orthodox, the Orientals must indicate their full and unqualified acceptance of seven ecumenical councils; they must accept not only the substance of the faith of these councils but also their disciplinary norms and terminology -- and presumably also their anathemas. For example, Patriarch Diodorus of Jerusalem in 1997 wrote a letter to Patriarch Ignatius of Antioch protesting, among other things, the latter’s eagerness to move forward to reunion on the basis of the work of the Joint Commission. “According to Holy Tradition,” Patriarch Diodorus avers, “the Non-Chalcedonians ought to accept absolutely and completely all the terms and canons of the Fourth Ecumenical Council of Chalcedon, in its entirety, as well as the following Fifth, Sixth, and Seventh Ecumenical Councils, also in their entirety.” 
For the Chalcedonian Orthodox, can the anathemas pronounced at councils four through seven be lifted? If so, how? This question sometimes has been approached from a juridical perspective: Who has the authority to lift an anathema? In this perspective, the answer would appear to be clear: An anathema can be lifted, but only by a body of the same or greater authority as the one which imposed it. The Joint Commission in 1993 urged that “the lifting of anathemas should be made unanimously and simultaneously by the heads of all churches of both sides.” But are “the heads of the all the churches” the juridically competent body? Not according to the memorandum from Mount Athos, which denounces this “decision of the Joint Commission concerning the possibility of lifting an anathema placed by an ecumenical council.” According to the memorandum, this is “alien to the sound mind of the Church” and “offends the fundamental consciousness of the Church concerning the authority of the ecumenical councils.” From this juridical perspective, only another ecumenical council would have the authority to lift the anathemas imposed by councils four through seven, though in a pinch presumably a Great and Holy Council of the Orthodox Church would do - when and if such a council meets.
But the issue of the anathemas - and along with it the issue of the number of ecumenical councils - is not simply a juridical question. It is a question of the identity and historical consistency of Orthodoxy itself, a question of the unity of the Church not only in space, with other professing Christians here and now, but in time, with the holy fathers and mothers of all ages. In this perspective, it becomes a matter of considerable significance whether one labels a given individual a saint or a heretic. As Metropolitan John Zizioulas has pointed out, membership in the Church does not mean simply the enjoyment of an a-temporal communion with Christ. It implies entering into communion with the saints of all the ages, as expresssed among other places in the diptychs, the calendar, and liturgical observances. And here by “saints” we should not think simply of those conspicuous for their personal sanctity. As Zizioulas points out, “saints are signs of the glory of God in this world not so much as individuals as in the context of the communion of saints, the advance guard of the One Body. ‘Saint’ therefore is a relational term; if relationship is broken -- if unity is broken -- the meaning of sanctity itself dramatically shifts.”  Can any body, even an ecumenical council, attempt to overturn the decision of a previous ecumenical council concerning who is a holy father and who is a heretic without calling into question the unity and continuity of the Church through time? This is the question which the memorandum from Mount Athos raises when it denounces “the attack upon the validity and authority of the Holy Ecumenical Councils by the decision of the Joint Commission that the Anti-Chalcedonian heresiarchs Dioscorus, Jacob, Severus, etc. be considered not heretical but Orthodox in their thinking.” As the memorandum continues, “The consciousness of the Orthodox Church recognizes that infallibility and authority in the Holy Spirit is in the ecumenical councils and refuses to accept the possibility of revising the decisions of an ecumenical council by another ecumenical council without the latter council being considered as an heretical conventicle...” 
How can one respond to such denunciations? Certainly ancient writers like Patriarch Eulogius of Alexandria would appear to be far more generous and forgiving. Here it is important to consider what kind of authority we ascribe to ecumenical councils. The memorandum from Mount Athos uses the word “infallibility.” This may be an unfortunate choice of words, the result of an understandable but regrettable reaction to Roman claims of papal infallibility. (We see here another example of the way in which ecclesial identity has, in the context of division, been formed by opposition, in this case by opposition to Roman Catholicism.) It would be more accurate to say simply that the ecumenical councils have inerrantly defined the faith and delineated the boundaries of true piety. But even if we speak of the “infallibility” of ecumenical councils, certainly this infallibility does not imply full and direct divine inspiration for each and every statement made in the course of these councils. It does not, for example, mean that councils and council fathers cannot be mistaken concerning matters of fact or inconsistent in their terminology. Councils - even ecumenical councils - do not invent or produce the faith of the Church. Rather, they bear witness to it. Therefore the adequacy of their words for this faith - and the appropriateness of their terminology and of their anathemas - must always be evaluated in the light of this faith.
Let us turn specifically to anathemas as these have been pronounced by successive ecumenical councils. These show an interesting progression as we move from earlier councils to subsequent councils. At the time when a given error or heresy is most pressing, an anathema, if pronounced, is usually quite specific about the position that is being condemned. The first ecumenical council at Nicaea, for example, reacting against the heresy which subsequent generations have called Arianism, concluded its creed with the following words: “And whosoever shall say that there was a time when the Son of God was not, or that before he was begotten he was not, or that he was made of things that were not, or that he is of a difference substance (hypostasis) or essence (ousia} [from the Father] or that he is a creature, or subject to change or conversion -- all that so say, the Catholic and Apostolic Church anathematizes them.”  As we come to later councils, the formulation becomes much less specific about the errors in question. Instead, it tends to be attached specifically to the person of Arius rather than to the position which he espoused: Anathema to Arius! We see a similar progression when it comes to other heresies. In the early stages of the Christological controversies, St. Cyril’s Twelve Anathematisms directed against the theology of Nestorius are quite specific. For example, the fourth anathematism reads: “If anyone shall divide between two persons or subsistences those expressions which are contained in the Evangelical and Apostolical writings, or which have been said concerning Christ by the Saints, or by himself, and shall apply some to him as to a man separate from the Word of God, and shall apply others to only the Word of God the Father, on the ground that they are fit to be applied to God: let him be anathema.”  These anathematisms were included verbatim in the acts of the third ecumenical council, Ephesus (431 A.D.), but thereafter formulations generally are content simply to anathematize Nestorius. In other words, a kind of theological “short-hand” develops. Instead of anathematizing a heretical position, which may be rather cumbersome to summarize and explain, we give this position a name and anathematize it as a heresy - Arianism or Nestorianism - or, more often, we associate it with a specific person and anathematize him - Arius or Nestorius.
In the case of Arius or Nestorius, the meaning of this “short-hand” is reasonably clear to the point of being self-evident. By saying “anathema to Nestorius” we are saying “anathema” to the positions denounced by St. Cyril in his Twelve Anathematisms and thereafter by the Council of Ephesus. But in some cases this “short-hand” can deceive. If we are very clear about what is being condemned, well and good. But if we rely simply on the “shorthand” of later councils, we may be misled. This point may be illustrated by reference to what Chalcedonian Orthodox regard as the sixth ecumenical council, III Constantinople (681 A.D.), which proclaimed anathema to Dioscorus “hated of God” and to the “impious” Severus of Antioch. This council was faced by the heresies of monotheletism and monenergism, which held that there was but one will and one natural energy in Christ. As frequently the case when faced with a new challenge, orthodox churchmen on the one hand denounced these heresies as dangerous innovations, but on the other they tried to demonstrate that the new heresies were simply old, long-condemned heresies in disguise. Like the monks of Mount Athos, like the fathers of the ancient councils generally, and for that matter like the heretics who assembled in the various ancient pseudo-councils, the fathers of III Constantinople wished to demonstrate the historical consistency of their own position and at the same time, the coherence of their opponents’ position with that of earlier heretics. Thus at III Constantinople the contemporary monothelites were seen as holding, among other things, the heresy of Apollinarius, who had held that Jesus Christ did not possess a human rational soul (nous) - a heresy which, according to III Constantinople, was condemned at I Constantinople (381 A.D.). In fact the story of I Constantinople is much more complex than a reading simply of the acts of III Constantinople would suggest; at I Constantinople itself, the question of Apollinarius’ teaching seems to have been tangential at most.  So also, at III Constantinople the monothelites were seen as holding the heretical positions condemned at Chalcedon and II Constantinople (553 A.D.), which the council associated respectively with Dioscorus and Severus, among others. Hence, in the course of a long series of anathemas pronounced at the final session of the council, we find the names of Dioscorus and Severus. Clearly, by the time of III Constantinople popular opinion did associate these names with heretical positions condemned at earlier councils. And this tendency continues in later centuries. For example, hymnography for the Feast of the Seven Ecumenical Councils (July 16 - originally the commemoration of the Council of Chalcedon) can exhort the orthodox to “abhor” Dioscorus and Severus along with a multitude of other heretics. But these formulations - these “short-hand” notes from later times - in fact are very misleading.
Let us first consider the case of Dioscorus. While III Constantinople can say anathema to Dioscorus and regard him as a progenitor of the monothelite heresy, this does not accurately reflect the views and activities of Dioscorus or how the Council of Chalcedon actually dealt with him. At that council Dioscorus was indeed deposed, but as the acts of the council indicate, “it was not for the faith that Dioscorus was deposed but because he had excommunicated the lord Leo, archbishop [of Rome], and that summoned three times, he did not come. This is why he was deposed.”  He did not in fact espouse the teaching of Eutyches, whose teaching concerning Christ and whose person were condemned at Chalcedon. To use the words of Fr. John Romanides, an Eastern Orthodox theologian deeply engaged in the theological dialogue with the Oriental Orthodox: “The backbone of the Orthodox tradition is the fact that the Logos became consubstantial with us. There can be no doubt that Dioscorus agrees with this fact and so could never be accused of being a monophysite along with Eutyches.”
Let us also consider the case of Severus. He clearly affirms the basic Christological truth that Jesus Christ is consubstantial with His Father in His divinity and consubstantial with us in His humanity. In other words, he does not fall into the heresy of Eutyches condemned at Chalcedon, which denied Christ’s consubstantiality with us and thus His full humanity. But Severus uses technical terms like hypostasis and physis in ways very different from the later formulations of Chalcedonian Orthodoxy. If read on his own terms, he is not guilty of either the heresy of monophysitism or the heresy of monotheletism as these have been condemned by the ecumenical councils.  His terminology may seem idiosyncratic, but it is hardly less so than that of most of his contemporaries, whether Chalcedonian (like Leontius of Byzantium) or Non-Chalcedonian. In other words, he was misunderstood, perhaps deliberately, perhaps inadvertently, by the time that Constantinople III labeled him “infamous” and anathematized him as one of the progenitors of monotheletism.
Here a further question may be posed. What weight should be given to an objection raised by Patriarch Diodorus in his letter to Patriarch Ignatius: “Are we to believe that they [viz., the theologians of the period in question] did not correctly understand those present in the Synods with whom they communicated in a common language and education?” But while it certainly is true that these theologians were working in the same language, Greek, it does not follow that they used technical terms - especially those with a philosophical coloring - in the same way. We sometimes face the same problem today. English now serves as an international language in much the way that Greek did in antiquity, but as a frequent participant in international meetings once remarked, “We live in a world in which everyone knows English -- bad English!” A concrete word like “shoe” will be understood in much the same way by virtually every speaker of the English language, even by those for whom English is a second language, but a word like “existential” or “natural” will mean different things to different people, even to those whose only language is English. And of course the problem becomes even more complicated in the case of theologians who worked in different languages.
The faith of the ancient councils - I Nicaea, I Constantinople, Ephesus, Chalcedon, II Constantinople, III Constantinople, II Nicaea - is consistent, whether one labels all seven or only the first three as ecumenical. But their terminology is not always consistent. I Nicaea, for example, used the words hypostasis and ousia as synonyms, while the later councils took great pains to distinguish them. So too, the anathemas of the ancient councils are not always consistent. Too often we have mistaken the “short-hand” of later periods for historical fact. The conclusion of the Joint Commission therefore is quite appropriate: “Both families agree that the lifting of anathemas and condemnations will be consummated on the basis that the Councils and fathers previously anathematized or condemned are not heretical” (1990 Chambesy Agreed Statement, para. 10). But will this happen any time in the foreseeable future?
The question at this point is whether we really desire unity more than our present disunity. Will we continue to be divided simply by the power of division itself? Certainly at the present time we seem to prefer the disunity of the status quo. Our cherished anathemas and preferred formulas give us a sense of security. Without them, our very identity seems threatened. Of course, much of Christian doctrine arose precisely because of the need to define the truth in opposition to heresy. But the words in which the truth are expressed are not the same as the truth itself. Failure to recognize this can lead to the kind of situation described by St. Gregory of Nazianzen. He notes how, when we try to lift a handful of water to our lips, some can be found slipping through our fingers:
In the same way, there is a separation not only between us and those who hold aloof in their impiety, but also between us and those who are most pious - a separation in regard both to such doctrines as are of small consequence and to expressions intended to bear the same meaning. 
Certainly this is the situation in which the Eastern Orthodox and Oriental Orthodox find themselves today. If our church families can overcome the division of centuries, if they can recognize in each other the same one faith, if they can enter into a life of communion in the deepest sense of that word, their reunion will be a sign of promise for all Christians.
 Participants included, among others, Georges Florovsky, John Meyendorff, John Karmires, John Romanides, John Zizioulas, Paul Verghese and V.C. Samuel.
 Reports of the four unofficial dialogues (1964-1971) are published in The Greek Orthodox Theological Review 10.2 (1964-65), 13 (1968), and 16.1 and 2 (1971).
 At this point the agreed statements and proposals of the Joint Commission are available in English translation most conveniently in St. Nersess Theological Review 1.1 (1996) 99-110.
 J. Lebon, Le monophysisme Severien (Louvain, 1909).
 On Severus’ Christology and its significance for dialogue today, see most recently John Behr, “Severus of Antioch: Eastern and Oriental Orthodox Perspectives,” St. Nersess Theological Review 3.1-2 (1998) 23-35.
 See especially his Christ in Eastern Christian Thought (Crestwood NY: St. Vladimir’s Seminary Press, 1975).
 Evagrius, Eccl. Hist. 5.4, cited by J. Meyendorff, Imperial Unity and Christian Divisions (Crestwood NY: St. Vladimir’s Seminary Press, 1989) 262.
 John of Ephesus, Hist. Eccl. 5.15, ed. and trans. E.W. Brooks (Paris - Louvain: 1935-36), cited by Meyendorff, Imperial Unity 264-5.
 La Narratio de Rebus Armeniae, ed. G. Garitte (Louvain: Peeters, 1952) 242-4, cited by M. Findikyan, “Liturgical Usages and Controversy in History: How Much Diversity Can Unity Tolerate?” St. Nersess Theological Review 1.2 (1996) 197, to whose discussion of liturgical diversity the present summary is deeply indebted. On this episode and others from this crucial period in Armenian ecclesiastical relations with Constantinople, see now Nina Garsoian, L’Eglise Armenienne et le grand schisme d’Orient (Louvain: Peeters, 1999), esp. 267-77.
 Girk’ Tlt’oc’ [Book of Letters], ed. J. Ismireantz (Tiflis: 1901) 475-76; French trans. with extensive commentary M. van Esbroeck, “Le discours du Catholicos Sahak III en 691 et quelques documents armeniens annexes au Quinisexte,” in The Synod in Trullo Revisited, ed. G. Nedungatt and M. Featherstone (Rome: Pontificio Istituto Orientale, 1995), 323-454 at 431; English trans. M. Findikyan, “Liturgical Usages...” 198-99.
 The canon in question takes pains to correct Sahak’s manifestly incorrect interpretation of a passage from St. John Chrysostom’s homilies on Matthew: Chrysostom was condemning the ancient sect of the Hydroparastatae, who substituted water for wine in the eucharist, not those who mix water with the wine. On this and other aspects of Sahak’s treatise and its importance in the history of Byzantine - Armenian relations, see van Esbroeck, “Le discours...” passim.
 On Sahak’s argument and Trullo’s response, see van Esbroeck, “Le discours...” passim.
 R.F.T[aft], “Trisagion,” in the Dictionary of Byzantium (Oxford: Oxford University Press, 1991) 2121; S.P. Brock, “The Thrice-Holy Hymn in the Liturgy,” Sobornost/Eastern Churches Review 7.2 (1985) 24-34; V.-S. Janeras, “Les byzantines et le trisagion christologique,” in Miscellanea liturgica in onore di sua eminenza il Cardinale Giacomo Lercaro 2 (Rome: 1967) 469-99.
 See T.J. Talley, The Origins of the Liturgical Year (New York: Pueblo, 1986) 168-222.
 Theoriani Disputationes com Armeniorum Catholico I, PG 133:204B, cited by A. Papadakis, The Christian East and the Rise of the Papacy (Crestwood NY: St. Vladimir’s Seminary Press, 1994) 116.
 Encyclical Letters of St. Nersess Shnorali (Jerusalem: 1871) 138, cited by M. Findikyan, “Liturgical Usages...” 207.
 The expression is that of Paul Magdalino, The Empire of Manuel I Komnenos, 1143-1180 (Cambridge: Cambridge University Press, 1993) 386-88 et passim.
 Communique of the Meeting of the Subcommittees on Liturgical and Pastoral Issues, 2-5 February 1998, Damascus, Syria, points 3 and 4 (typescript). The English text - practically incomprehensible in the original press release - has been lightly modified for greater grammatical and lexical clearity.
 See, for example, John Meyendorff, “Chalcedonians and Non-Chalcedonians: The Last Steps to Unity,” St. Vladimir’s Theological Quarterly 33.4 (1989) 319-329; Thomas FitzGerald, “Toward the Reestablishment of Full Communion: The Orthodox-Orthodox Oriental Dialogue, “Greek Orthodox Theological Review 36.2 (1991) 169-181; Theodore Pulcini, “Recent Strides Toward Reunion of the Eastern and Oriental Orthodox Churches: Healing the Chalcedonian Breach,” Journal of Ecumenical Studies 30.1 (1993) 34-50.
 In Orthodox Life 45.3 (1995) 39-41, where it is followed by a lengthy critique of the work of the Joint Commission and of the churches participating in it.
 Ser. no. ph2/116/455, May 14/27, 1995 - typescript.
 See the trenchant critique of the memorandum by A. Golitzin, “Anathema! Some Historical Perspectives on the Athonite Statement of May, 1995,” St. Nersess Theological Review 3.1-2 (1998) 103-117, especially 106-9.
 The Ethiopian Tewahido Church (New York?: n.d.) 108.
 Letter no. 361, May 17, 1997.
 “Ecclesiological Issues Inherent in the Relations Between Eastern Chalcedonian and Oriental Non-Chalcedonian Churches,” Greek Orthodox Theological Review 16 (1971) 144-62 at p. 149.
 Cf. the extremely valuable assessment of D. Wendebourg, “Chalcedon in Ecumenical Discourse,” Pro Ecclesia 7.3 (1998) 307-332 at p. 330: “Why is so much made of the question, ‘Three or seven ecumenical councils?’ if a consensus has nevertheless been reached on the substance of Christology? This question is of such great importance because it is directly concerned with the identity of the divided churches, identity understood not simply in a psychological sense, but in a theological one. It is a matter of the relation of the presence of the Holy Spirit in the church to the concrete history of the church. Both sides concede to each other that they are legitimate representatives of faith in Christ, and that means filled with the Holy Spirit. But each side has existed for fifteen hundred years in a distinctive way, characterized - positively - by a distinctive expression of faith in Christ and negatively - by being distinguished from those who do not share this exposition. Can the concrete historical form of their path under the guidance of the Spirit be detached from a ‘substance’ of the presence of the Spirit without this presence of the Spirit becoming a purely abstract reality?”
 Trans. Nicene and Post-Nicene Fathers, ser. 2, vol. 14, 3.
 Ibid. 211.
 For a convenient presentation of I Constantinople see Archbishop Peter L’Huillier, The Church of the Ancient Councils: The Disciplinary Work of the First Four Ecumenical Councils (Crestwood NY: St. Vladimir’s Seminary Press,1996) 101-42.
 Patriarch Anatolius of Constantinople, in Session 5, quoted by L’Huilllier, Church of the Ancient Councils 189, with further discussion of the case of Dioscorus.
 “Leo of Rome’s Support of Theodoret, Dioscorus of Alexandria’s Support of Eutyches, and the Lifting of the Anathemas,” paper (as yet unpublished?) presented at the November 1993 meeting of the Joint Commission for Theological Dialogue Between the Orthodox Church and the Oriental Orthodox Churches (Geneva) 6.
 On this subject see most conveniently John Behr, “Severus of Antioch...” 23-35.
 Or. 21.35.
"The true Christian is a warrior making his way through the regiments of the invisible enemy to his heavenly homeland." - St Herman of Alaska.