These two letters, which are the earliest of Chrysostom's extant works, are addressed to a friend who had been a member of the little ascetic brotherhood which Chrysostom and Basil formed, soon after they had abandoned secular life, as described in the first book of the Treatise on the Priesthood. Theodore, like Maximus, afterwards Bishop of Isaurian Seleucia, who was another member of the same fraternity, had been a fellow student with Chrysostom and Basil in the school of Libanius, but was a few years younger than either of them. The strain upon his powers of religious devotion had proved too much for him; he had withdrawn from the ascetic brotherhood, and relapsed for a season into worldly habits, being fascinated by the beauty of a young lady named Hermione, whom he was anxious to marry. His fall was regarded with almost as much sorrow and dismay by his austere friends as if he had plunged into deadly vice. Prayers were continually offered, and great efforts made for his restoration, amongst which must be reckoned the two letters which are here translated. They are the productions of a youthful enthusiast, and as such allowances must be made for them; but they abound in passages of great beauty and power, especially upon the infinite love and forbearance of God, as encouraging to repentance and withholding from despair and recklessness into which Theodore seems to have been inclined to sink. The appeal of Chrysostom, combined with the efforts of his other friends, was not in vain. Theodore once more renounced the world and his matrimonial intentions, and retired into the seclusion of the fraternity. In A.D.383, when he was about thirty-three years of age, he was ordained priest, and in 392 he became Bishop of Mopsuestia, where he died in A.D.428 at the age of seventy-eight. Chrysostom seems to have retained his affection to him to the last, and during his own exile at Cucusus, A.D.404-7, wrote a letter to him which is full of expressions of fervent admiration and regard. He was a most voluminous writer, and may be regarded as the ablest representative of the school of Biblical interpretation founded by Diodorus of Tarsus, under whom he had studied, together with Chrysostom and Basil. A fierce controversy raged during the fifth and sixth centuries respecting the orthodoxy of some of his writings which some accused of preparing the way for Nestorianism. When this had died down his name was comparatively forgotten, and it is only in modern times that his great merits as a commentator, who boldly applied the historical and grammatical methods of examination to the books of Holy Scripture, have been fully recognized.
Tillemont was of opinion that of the two letters of Chrysostom the second only was addressed to Theodore, who was afterwards Bishop of Mopsuestia. Montfaucon, however, Dupin, and Savile, maintain that both were addressed to him, and their view is confirmed by the fact that Leontius of Byzantium (in Nest. et. Eutych. lib. iii. c.7) and Isidore of Seville (de Script. Eccl. c.6.) mention two letters of Chrysostom to Theodore of Mopsuestia.