The Arian crisis

Doctrinal · 325–381 · ecumenical

Sixty years of argument about whether the Son is God in the same sense the Father is. Nicaea answered it in one word and did not end it: the next two generations saw the word defended by a minority, rejected by councils, imposed and withdrawn by emperors, and finally received in 381 by a council of a hundred and fifty bishops in a city where the cathedral had been Arian for forty years.

How it ended. The Nicene faith stands, reaffirmed at Constantinople in 381, and the parties that fought it are named and set aside in its first canon.

How it ran

  1. 325 — First Council of Nicaea (where it hardened). Condemns Arius and puts homoousios into the creed.
  2. 335 — First Synod of Tyre (where it hardened). Deposes Athanasius on charges the council would not test.
  3. 343 — Council of Sardica (where it hardened). Called to settle it and split into two councils that condemned each other.
  4. 359 — Council of Ariminum (where it hardened). Subscribes the Dated Creed under imperial pressure.
  5. 359 — Council of Seleucia in Isauria (where it hardened). The Eastern half of the same double council, sitting the same year.
  6. 381 — First Council of Constantinople (where it was settled). Reaffirms the Nicene faith and names the parties it sets aside.

What was at issue

Who stood in it

What was written

After The Seven Ecumenical Councils (NPNF series 2 vol. 14) · Constantinople I (381), canon 1.