The First Council of Nicaea, held in Nicaea in Bithynia (present-day Iznik in Turkey), convoked by the Roman EmperorConstantine I in 325, was the first Ecumenical council of the early Christian Church, and most significantly resulted in the first uniform Christian doctrine, called the Nicene Creed. With the creation of the creed, a precedent was established for subsequent 'general (ecumenical) councils of Bishops' (Synods) to create statements of belief and canons of doctrinal orthodoxy— the intent being to define unity of beliefs for the whole of Christendom. The Council of Nicaea was historically significant because it was the first effort to attain consensus in the church through an assembly representing all of Christendom. "It was the first occasion for the development of technical Christology." Further, "Constantine in convoking and presiding over the council signaled a measure of imperial control over the church." Further, a precedent was set for subsequent general councils to create creeds and canons. The long-term effects of the Council of Nicaea were significant. For the first time, representatives of many of the bishops of the Church convened to agree on a doctrinal statement. Also for the first time, the Emperor played a role, by calling together the bishops under his authority, and using the power of the state to give the Council's orders effect.
Chrysostom is known in Christianity chiefly as a preacher, theologian and liturgist, particularly in the Eastern Orthodox Church. Among his sermons, eight directed against the Jews remain controversial for their impact on the development of Christian antisemitism.