THEOGNOSTUS. - Archimandrite, a faithful and most loyal friend of St IGNATIUS, Patriarch of Constantinople; in 862 he brought to Pope NICHOLAS I a written defence (*libellus*) of his patriarch and remained in Rome until 868.
He left a panegyric on the Saints and a homily on the Dormition (Assumption) of the Blessed Virgin Mary. He probably died at the end of the 9th century.
BIBL.: PG 105, pp. 849-62; M. Jugie, Théognoste, in D’H. XV, pp. 337-38; the homily on the Dormition of the Blessed Virgin Mary was edited by M. Jugie in PO XIV, 457-62. Giorgio Hofmann