On 17 July 2010, Abba Seraphim, accompanied by Deacon Theodore de Quincey, attended an Ecumenical Service at Westminster Cathedral in celebration of the 400th Anniversary of the Martyrdom of St. John Roberts.

John Roberts (1577-1610) was a Welsh gentleman, descended from the ancient British kings, who was educated at St. John’s College, Oxford, and studied law in London. Although raised a Protestabnt he converted to Catholicism and studied at the English College at Vallodolid in Spain. He was professed as a Benedictine monk as Brother John of Merioneth. Ordained a Catholic priest he became a frequent visitor to England where he celebrated the mass and ministered to persecuted Catholics in London, especially during outbreaks of the Plague. He was arrested and imprisoned on several occasions and deported but each time returned. For exercising his priesthood he was found guilty of high treason and executed at the age of 33 years. Commenting on the celebration Abba Seraphim noted that as a Londoner he wanted to honour the humanitarian and pastoral ministry of the saint to Londoners; and that all those who are conscious of the problems of exercising Christian ministry in times of persecution would immediately value the saint’s determination as well as realising the extraordinary sacrifice he made to fulfil his priestly vocation.

Leading this eirenic celebration were the Catholic  Archbishop of Westminster (Mgr. Vincent Nichols), the Archbishop of Canterbury (Dr. Rowan Williams), the Anglican Archbishop of Wales (The Most Rev’d Barry Morgan) and the Catholic Bishop of Wrexham (Mgr. Edwin Regan) with many other Catholic and Anglican bishops from Wales. Other Orthodox Churches were represented by His Grace Bishop Athanasios of Tropaeou (Oecumenical Patriarchate), Archbishop Elisey of Sourozh (Moscow Patriarchate), The Very Rev’d Archimadrite of the Oecumenical Throne Ephrem (Lash) and Archimandrite Deiniol, Administrator of the Wales Orthodox Mission (Ukrainian Orthodox Church within the Oecumenical Patriarchate). Large contingents from Wales were in enthusiastic attendance and the service was bi-lingual.