Theodore.AidanHart.400 Published September 18, 2011 at 400 × 543 in Morning Prayer 19 September 2011, St Theodore of Tarsus, Archbishop of Canterbury, 690 Aidan Hart: St. Theodore. He was an Eastern monk and a regularizer. He established an excellent school at Canterbury and drew diocesan and parochial boundaries so the Church could be effectively ministered to – that is, administered.