Severus, founder of the Gnostic sect named after him Severians (q.v.). He came from Sozopolis to Pisidia, and while a pagan was a lawyer. Receiving baptism at Tripoli, in Phoenicia, he became a monk and united himself with a society of zealous Monophysites. Banished, he came to Constantinople to seek protection from the emperor. He told him that the defense of the Chalcedonian Council was the cause of all the disturbances, and sought to introduce a certain addition to the old and venerated Church song the Trisagion which might serve as the basis of a coalition between the opposing parties. Later, in the reign of Justin, Severus, who had managed to become patriarch of Antioch, saved his life by fleeing to Egypt. He returned to Constantinople with Anthimus, under the protection of the empress Theodora; but Justinian, finding that he had been imposed upon by the Monophysites, deposed Anthimus, and decreed that "the writings of Severus should be burned, and none should be permitted either to own or transcribe them." See Neander, Ch. Hist. 2, 531 sq.