The Second Ecumenical Council:  The First Council of Constantinople 3Canon I.

Canons of the One Hundred and Fifty Fathers who assembled at Constantinople during the Consulate of those Illustrious Men, Flavius Eucherius and Flavius Evagrius on the VII of the Ides of July. The Bishops out of different provinces assembled by the grace of God in Constantinople, on the summons of the most religious Emperor Theodosius, have decreed as follows:

Canon I. The Faith of the Three Hundred and Eighteen Fathers assembled at Nice in Bithynia shall not be set aside, but shall remain firm. And every heresy shall be anathematized, particularly that of the Eunomians or [Anomaeans, the Arians or] Eudoxians, and that of the Semi-Arians or Pneumatomachi, and that of the Sabellians, and that of the Marcellians, and that of the Photinians, and that of the Apollinarians.