The dispute over the date of Pascha

Calendrical · 325 · ecumenical

Whether Pascha follows the fourteenth of the moon on whatever day it falls, as the churches of Asia held, or waits for the Sunday. Victor of Rome tried to break communion over it and was rebuked by Irenaeus for trying.

How it ended. Nicaea ruled for the Sunday and for one date everywhere, and fixed no arithmetic — which is why the argument came back as a computistical one for four centuries.

After The Seven Ecumenical Councils (NPNF series 2 vol. 14) · Nicaea I (325), the synodal letter to the Alexandrians.