ISAIAH. — Ascetic writer, not to be confused with the Egyptian monk ISAIAH of the 4th century, of whom Rufinus (Hist. monarch., 10; PL 21, 428 ff.; cf. E. Preuschen, Palladius und Rufinus, Giessen 1897, p. 63 ff.) and Palladius (Hist. Lausia, ch. 14; ed. Butler, II, p. 37 ff.) speak. ISAIAH was a Monophysite, also an ascetic; he came from Egypt to Palestine, living in the region of Eleutheropolis and near Gaza, where he died on 11 Aug. 488. According to Zacharias Rhetor (Vita Isaiae, ed. E. W. Brooks, Corpus script. christ. orient., Script. Syri, 3rd ser., XXV, Paris 1907, Latin trans., pp. 1-10), he was also the author of ascetic writings.
His relations as a Monophysite with PETER THE IBERIAN, bishop of Maiuma, and with THEODORE OF ANTINOE are well attested; but his true position