Byzantine monk, theologian, and advocate of reunion; b. Constantinople, 1197; d. Emathia, near Ephesus, 1272. In 1205 he left Constantinople, soon after its fall to the Crusaders (1204). In the course of several years he acquired encyclopedic knowledge through his studies at Prusa, Nicaea, Ephesus, Smyrna, and other cities. In 1223 he became a member of the clergy of Nicaea. In 1232, at Nicaea, and in 1234, at Nymphaeum, he took part in the theological discussions with the Latin legates. He composed a tract defending the Greek position, which occasioned the failure of the negotiations then and again in 1250. He was entrusted with the education of the future Emperor Theodore II Lascaris and of George Akropolites, founded the monastery of Emathia near Ephesus (1248), and refused the bishopric of that city as well as the patriarchate of Nicaea offered to him by his former pupil Theodore. Toward 1256 he accepted the conciliatory attitude toward the Latins adopted by the emperor, apparently influenced by the Dialogues on the Procession of the Holy Spirit written by Nicetas of Maronia, and he interpreted the phrase "per filium" in an anti-Photian sense. However, in his autobiography, written in 1264, he repudiated any compromise with the Latins.
Preserved in two recensions, the autobiography is the chief work of his abundant literary production, which included two controversial tracts on the procession of the Holy Spirit, a testament for his monks "Against the Filioque," commentaries, scholia on the Psalms with an interesting introduction (προοίμιον) on ecclesiastical chant, an encomion of St. John the Evangelist that is a dogmatic dissertation on Johannine theology, and several manuals of philosophy.
Bibliography: Patrologia Graeca 142. v. grumel, Dictionnaire de théologie catholique 11.1:441–445; Catholicisme 2:85–86. h. g. beck, Lexikon für Theologie und Kirche 2 7:970. Kirche und theologische Literatur im byzantinischen Reich 671–673. g. mercati, Bessarione 31 (1915) 226–238; Opere minore, 5 v. (Studi e Testi 76–80; 1937–41); "… Commento del Salterio," Biblica 26 (1945) 153–181. h. i. bell, "The Commentary on the Psalms," Byzantinische Zeitschrift 30 (1929–30) 295–300.