First Council of Nicaea

Christianity [325]
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Quick Facts
Date:
325
Location:
İznik
Turkey
Participants:
history of early Christianity
Top Questions

What was the significance of the Council of Nicaea?

Did the Council of Nicaea settle the matter of Arianism?

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First Council of Nicaea, (325), the first ecumenical council of the Christian church, meeting in ancient Nicaea (now İznik, Turkey). It was called by the emperor Constantine I, an unbaptized catechumen, who presided over the opening session and took part in the discussions. He hoped a general council of the church would solve the problem created in the Eastern church by Arianism, a heresy first proposed by Arius of Alexandria that affirmed that Christ is not divine but a created being. Pope Sylvester I did not attend the council but was represented by legates.

The council condemned Arius and, with reluctance on the part of some, incorporated the nonscriptural word homoousios (“of one substance”) into a creed to signify the absolute equality of the Son with the Father. The emperor then exiled Arius, an act that, while manifesting a solidarity of church and state, underscored the importance of secular patronage in ecclesiastical affairs.

The council attempted but failed to establish a uniform date for Easter. It issued decrees on many other matters, including the proper method of consecrating bishops, a condemnation of lending money at interest by clerics, and a refusal to allow bishops, priests, and deacons to move from one church to another. It also confirmed the primacy of Alexandria and Jerusalem over other sees in their respective areas. Socrates Scholasticus, a 5th-century Byzantine historian, said that the council intended to make a canon enforcing celibacy of the clergy, but it failed to do so when some objected.

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The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Melissa Petruzzello.