First Council of Nicaea

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.

Arianism

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Arius was an ascetical moral leader of a Christian community in the area of Alexandria. He attracted a large following through his message integrating Neoplatonism, which accented the absolute oneness of the Divinity as the highest perfection, with a literal, rationalist approach to the New Testament texts. This point of view was publicized about 323 through the poetic verse of his major work, Thalia (“Banquet”), and was widely spread by popular songs written for laborers and travelers.

With the rise of Arianism as the impetus, the First Council of Nicaea was largely convened to resolve the controversy over the relationship between the persons of the Trinity. The council condemned Arius as a heretic after he refused to sign the formula of faith stating that Christ was of the same divine nature as God. Constantine then exiled Arius, an act that, while manifesting a solidarity of church and state, underscored the importance of secular patronage in ecclesiastical affairs.

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Jesus: Nicaea

To further define orthodoxy, the council (with reluctance on the part of some) incorporated the nonscriptural word homoousios (Greek: “of one substance”) into a creed to signify the absolute equality of the Son with the Father. Although the use of homoousios was meant to put an end to the controversy, the influence of Arianism persisted in the church for centuries. See also Nicene Creed.

Other issues

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.