Priscillian (prĭsĭl`yən), d. 385?, Spanish churchman, bishop of Ávila. His appointment to the bishopric was protested by orthodox leaders, who had condemned his former activities as a lay preacher in S Spain, at the Synod of Zaragoza (380). Although Priscillian's ideas were repeatedly denounced, it is not clear that they were heretical. He was suspected of Manichaean and Gnostic leanings because he stressed puristic ideals, sought perfection in asceticism, and dabbled in astrology. The church had been attacking his views for some time when Roman Emperor Maximus ordered that Priscillian be put to death for practicing magic. His execution was strongly protested by his former opponents in the church, St. Ambrose, St. Martin, and the pope. After his death Priscillian was venerated as martyr and saint, and his followers grew. Not until after a council held at Braga (563?) finally condemned Priscillianism did it disappear from Spain.