DIADOCHUS OF PHOTICE

Fifth-century bishop and anti-Monophysite theologian; d. before 486. Nothing is known of the life of Diadochus other than that he signed the response of the bishops of Epirus in Greece to the encyclical letter of Emperor leo i in 457 (J. D. Mansi, Scaorum Conciliorum nova et amplissima collectio 7.619; Acta conciliorum oecumenicorum 2.5.95), thus indicating his adherence to the Council of chalcedon. He is mentioned as an adversary of monophysitism by Photius (Bibl. cod. 231); and his death is recorded in the prologue to Victor of Vita's history of the Vandal persecution. The main work of Diadochus is the Capita centum de perfectione spirituali, or 100 chapters on spiritual perfection. It is a treatise that begins with ten definitions of virtues, following a common literary genre for such compositions. It deals with the discernment of spirits (ch. 26–35), the difficulties of contemplation (ch. 69–75), the theology of grace (ch. 76–89), the two stages of spiritual desolation (ch. 86–87), and the doctrine of man's creation in the image and likeness of God (ch. 89). Diadochus is also considered the author of the sermon for the Ascension, and a collection of questions and answers concerning the spiritual life under the title The Vision of John the Baptist.

In his ascetical doctrine Diadochus stressed the practice of the presence of God and the jesus prayer, following the tradition of evagrius ponticus. He is also thought to have opposed the Messalians, using the pseudo-Macarian homilies as a source. Certain difficulties have been encountered in his concepts, for he seems at times to use the technical language of the Messalians when referring to the supernatural. This gave rise to a confusion between grace as a theological concept and its consequence in the psychological order. His work on spiritual perfection had an influence on maximus the confessor, symeon the new theologian, teresa of avila, and ignatius of loyola, as well as on the 18th-century Oriental collection of spiritual writers known as the Philocalia.

Bibliography: Oeuvres spirituelles, ed. and tr. É. des places (Sources Chrétiennes 5; 1955). f. dÖrr, Diadochus von Photike und die Messalianer (Freiburg 1937). h. marrou, Revue des études anciennes 45 (1943) 225–232, Victor de Vita. e. honigmann, Patristic Studies (Studi e Testi 173; 1953) 174–184. b. altaner, Patrology, tr. h. graef from 5th German ed. (New York 1960) 391. h. g. beck, Kirche und theologische Literatur im byzantinischen Reich (Munich 1959) 360–361.

[É. des places]