Abstract

The Synod of Mar Ishaq (410) seems to be an Oriental version of Constantine's reforms. In both cases, peace is established in the relations between Christians and the Empire: the community is unified by one doctrine and one disciplinary custom ratified by a Synod and by the Emperor. Yet the similarities between Constantine and Yazdgard subtend a historical context in which the role of Marutha of Maypherqat, the Roman ambassador to the Sasanian court, stands out. His action, in the ever-uncertain circumstances of history, pursues the 'all-round' success of the Church, both in the East and in the West. Hence, the Synod distinguishes itself not so much in its proud claim to the East's autonomy from the West as in the implicit fulfillment of Ecumenical dialogue and in the sharing of texts: despite the length of the period concerned (325-410), the reception of the Nicene declaration of faith and of the canons provides proof of the common efforts to bear witness to a reliable, well-ordered Christian life in history.