Arianism is the theological teaching attributed to Arius (ca. AD 250–336), a Christian presbyter in Alexandria, Egypt, concerning the relationship of God to the Son of God (Jesus of Nazareth). Arius asserted that the Son of God was a subordinate entity to God the Father. Deemed a heretic by the Ecumenical First Council of Nicaea of 325, Arius was later exonerated in 335 at the regional First Synod of Tyre,[1] and then, after his death, 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.
The Arian concept of Christ is that the Son of God did not always exist, but was created by—and is therefore distinct from—God the Father. This belief is grounded in the Gospel of John passage “You heard me say, ‘I am going away and I am coming back to you.’ If you loved me, you would be glad that I am going to the Father, for the Father is greater than I." (verse 14:28)
