ISTANZIO. — Among the disciples of Priscillian, Bishop I. deserves special attention because to him have been attributed, more than to the leader of the sect, the 11 treatises discovered by G. Schepss and published in CSEL, 18 (1889). Written from an apologetic standpoint, they do not contain anything of great significance that reveals the heresy of which Priscillian’s contemporaries accused him. For this reason, Morin attributed them to I., but not all were satisfied with the solution proposed by the learned Benedictine scholar; and the authorship of the aforementioned treatises remains a matter of debate.
BIBL.: G. Morin, Pro I. contre l'attribution à Priscillien des opuscules du manuscrit de Würzburg, in Rev. bénédictine, 30 (1913), pp. 153-73. Against Morin stands J. Martin, Priscillian oder I., in Hist. Jahrbuch, 33 (1912), pp. 237-51. Giuseppe Madox.