Background
Theodore was born in Constantinople in 759. He was the oldest son of Photeinos, an important financial official in the palace bureaucracy, and Theoktiste, herself the offspring of a distinguished Constantinopolitan family.
Theodore was born in Constantinople in 759. He was the oldest son of Photeinos, an important financial official in the palace bureaucracy, and Theoktiste, herself the offspring of a distinguished Constantinopolitan family.
In 794 he succeeded his uncle Platon, who had persuaded him to become a monk some ten years before, as head of the monastery of Saccudium in Bithynia. Soon afterwards he was banished to Thessalonica for having excommunicated Constantine VI, who had divorced his wife Maria in order to marry Theodote. After the emperor's death in 797 he was recalled with every mark of favour, and removed with his monks to the monastery of Studium in Constantinople, where he carried on a vigorous campaign in favour of asceticism and monastic reform. In 809 he was again banished in consequence of his refusal to hold communion with the patriarch Nicephorus, who had pardoned the priest Joseph for his part in the marriage of Constantine and Theodote. In 811 he was recalled by Michael Rhangabes, and again banished in 814 for his resistance to the edict of Leo the Armenian, which forbade the worship of images. Liberated in 821 by the Emperor Michael the Stammerer (Balbus), he soon got into trouble again. In 824 he violently attacked Michael for showing too great leniency towards the iconoclasts and even favoured an insurrection against him. When the attempt failed, Theodoras found it prudent to leave Constantinople. He lived at various monasteries in Bithynia, on Chalcitis (one of the Princes' Islands) and on the peninsula of Tryphon, near the promontory of Acrita, where he died on the 11th of November 826. He was buried at Chalcitis, but his body was afterwards (26th of January 844) removed to Studium. He subsequently received the honours of canonization. Of his extant works the following are the most important: Letters, which are of considerable value as giving an insight into the life and character of the writer, and throwing light upon the ecclesiastical disputes in which he was involved; Catecheses (divided into Magna and Parva), two collections of addresses to his monks on various subjects connected with the spiritual life; funeral orations on his mother and his uncle Plato; various polemical discourses connected with the question of image-worship. He was also the author of epigrams on various subjects, which show considerable originality, and of some church hymns.
Theodorus died on the 11th of November of 826, while celebrating mass, apparently in the monastery of Hagios Tryphon on Cape Akritas in Bithynia. Eighteen years later, his remains, along with those of his brother Joseph, were brought back to the Stoudios Monastery, where they were interred beside the grave of their uncle Platon.