Arianism

Arianism, in Christianity, is a Christological concept that asserts that Jesus Christ is the Son of God who was created by God the Father at a point in time, is distinct from the Father and is therefore subordinate to the Father. Arian teachings were first attributed to Arius (c. AD 250–336), a Christian presbyter in Alexandria, Egypt. The teachings of Arius and his supporters were opposed to the prevailing theological views held by proto-orthodox Christians, regarding the nature of the Trinity and the nature of Christ. The Arian concept of Christ is that the Son of God did not always exist but was created by God the Father.

Homoousianism was formally affirmed by the first two Ecumenical Councils. All mainstream branches of Christianity therefore consider Arianism to be heterodox and heretical. The Ecumenical First Council of Nicaea of 325 deemed it to be a heresy. At the regional First Synod of Tyre in 335, Arius was exonerated. After his death, he was again anathemised and pronounced a heretic again at the Ecumenical First Council of Constantinople of 381. The Roman Emperors Constantius II (337–361) and Valens (364–378) were Arians or Semi-Arians, as was the first King of Italy, Odoacer (433?–493), and the Lombards till the 7th century.

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