the doctrine of Arius, pronounced heretical at the Council of Nicaea, which asserted that Christ was not of one substance with the Father, but a creature raised by the Father to the dignity of Son of God
either of two church councils that met at Nicaea, the first in a.d. 325 to deal with the Arian heresy, the second in a.d. 787 to consider the question of the veneration of images.
