Constantine Paid for 300 Bishops to Attend a Two-Month Council and Decide What Christians Believe

In the spring of 325 AD, the emperor Constantine summoned the first ecumenical council of the Christian church to the Bithynian city of Nicaea — modern İznik, Turkey. The empire was a recently Christian one. Constantine had granted toleration with the 313 Edict of Milan, but the church his patronage was now consolidating was visibly fractured along multiple theological lines. The most explosive was a dispute that had begun in Alexandria around 318: the presbyter Arius taught that Christ, while divine, was a created being subordinate to the Father, and his bishop Alexander argued the opposite. Constantine, who cared less about the metaphysics than the cohesion of his own state church, paid for travel, lodging, and meals for as many bishops as cared to attend, and convened them in late spring 325. Tradition gives the count as 318 — a number convenient because it matches the household of Abraham in Genesis. Modern estimates put the actual count between 250 and 300. The council ran from late May until the end of July.

The council's main work was the doctrine. After lengthy debate it produced the Nicene Creed, which described Christ as "begotten not made, of one substance with the Father" — language carefully chosen to exclude Arius. Two of Arius's supporters refused to sign and were exiled with him to Illyria. The council also separated the calculation of Easter from the Jewish Passover, which had been the previous practice in many eastern churches, and issued twenty new disciplinary canons.

What the council did not do is settle the issue. Arianism survived for several centuries; later Roman emperors, including Constantine's own son Constantius II, embraced versions of it. The Nicene Creed itself was substantially revised at a second council in Constantinople in 381, and the version most Christians today recite as "the Nicene Creed" is actually the 381 revision.