Basil the Physician († 1118) was the Bogomil leader condemned as a heretic by Patriarch Nicholas III of Constantinople and burned at the stake by Byzantine Emperor Alexius I Comnenus. Basil first came to the attention of the emperor after imperial officers had tortured a member of the Bogomil sect to reveal the identity of their leader. He admitted that Basil was their leader and that he had selected twelve teachers to act as his apostles. This sect, noted for their Manichean tendencies, Iconoclastic principles and their detestation of the Orthodox hierarchy, had been rapidly gaining adherents throughout Alexius’ reign, and began to cause alarm among the Byzantine clergy. Eager to confront this threat, he was ordered to appear before the emperor.