Didymus the Blind, of Alexandria, b. about 310 or 313; d. about 395 or 398, at the age of eighty-five. Didymus lost the use of his eyes when four years old, yet he became one of the most learned men of his period. He prayed earnestly in his youth, we are told by Rufinus, not for the sight of his bodily eyes, but for illumination of the heart. He admitted to St. Anthony that the loss of his sight was a grief to him; the saint replied that he wondered how a wise man could regret the loss of that which he had in common with ants and flies and gnats, and not rather rejoice that he possessed a spiritual sight like that of the saints and Apostles. St. Jerome indeed habitually spoke of him not as “the blind” but as “the Seer”. Didymus studied with ardor, and his vigils were long and frequent, not for reading but for listening, that he might gain by hearing what others obtain by seeing. When the reader fell asleep from weariness, Didymus did not repose, but as it were chewed the cud (says Rufinus) of what he had heard, until he seemed to have inscribed it on the pages of his mind. Thus in a short time he amassed vast knowledge of grammar, rhetoric, logic, music, arithmetic, and geometry, and a perfect familiarity with Holy Scripture. He was early placed at the head of the famous catechetical school of Alexandria, over which he presided for about half a century. St. Athanasius highly esteemed him. The orator Libanius wrote to an official in Egypt: “You cannot surely be ignorant of Didymus, unless you are ignorant of the great city wherein he has night and day been pouring out his learning for the good of others.” He is similarly extolled by his contemporaries and by the historians of the following century. Rufinus was six years his pupil. Palladius visited him four times in ten years (probably 388-398). Jerome came to him for a month, in order to have his doubts resolved with regard to difficult passages of Scripture. Later ages have neglected this remarkable man. He was a follower of Origen, and adopted many of his errors. Consequently, when St. Jerome quarrelled with Rufinus and made war on Origenism, he ceased to boast of being a disciple of Didymus and was ashamed of the praise he had formerly given to the “Seer”. When Origen was condemned by Justinian and then by the Fifth General Council, Didymus was not mentioned. But he was anathematized together with Evagrius Ponticus in the edict by which the Patriarch Eutychius of Constantinople gave effect to the decree of the council; and he was (perhaps in consequence of this) included in the condemnation of Origenists by the sixth and seventh councils. But this censure is to be taken as applying to his doctrine and not to his person. It has had the unfortunate effect of causing the loss to us of most of his very numerous writings, which, as the works of a supposed heretic, were not copied in the Middle Ages.
Didymus always remained a layman. The idea that he was married rests on a mistaken identification of him with a Didymus to whom one of the letters of St. Isidore of Pelusium is addressed. He seems on the contrary to have lived the life of an ascetic, although in the city and not in the desert. A curious story was told by him to Palladius. One day, when dwelling on the thought of Julian as a persecutor, and on this account having taken no food, he fell asleep in his chair and saw white horses running in different directions, while their riders cried out: “Tell Didymus, today at the seventh hour Julian died; arise and eat, and inform Athanasius, the bishop, that he also may know it.” Didymus noted the hour and the month and the week, and it was even so.
Doctrine.—Didymus was one of the principal opponents of Arianism. His Trinitarian and Christological doctrine is perfectly orthodox; one may even say that he is more explicit than St. Athanasius as to the Unity in Trinity and the Divinity of the Holy Ghost. He has combined the theological vocabulary of St. Athanasius with that of the younger generation, Basil and Gregory Nazianzen. He continually uses the formula treis hupostaseis, mia ousia, which St. Athanasius admitted in his later years, and which has become the Catholic watchword. Didymus has been credited with the invention of this formula, and Leipoldt is in favor of the attribution, whereas K. Holl rejects it. Until the fourth century the Greek-speaking Church had no means of expressing the doctrine of of the Trinity. The use of hupostasis to express the Latin persona was in itself a clumsy device, for Didymus agrees with St. Jerome (who rejected the expression) that philosophically ousia and hupostasis are synonyms. Didymus, however, carefully safeguarded his doctrine from any wrong interpretation. His work on the Holy Spirit is preserved only in the Latin translation made by St. Jerome. It is free from the reproach of “economy” which attaches to the more famous work of St. Basil, who avoided (as he himself admits) calling the Holy Ghost “God“. A yet more important work is the “De Trinitate”, the three books of which are preserved almost entire; it was composed after 379. A treatise against the Manichans is also nearly complete. Of the exegetical fragments, those on the Psalms are the most important. A commentary on the Catholic Epistles is known to us through the Latin translation made by a certain Epiphanius for Cassiodorus. Didymus comments on II Peter, and elsewhere frequently quotes that Epistle, although in one place he declares it to be spurious (falsata—the Greek is lost). In his commentaries Didymus shows himself to be much influenced by Origen, both in his care for the text and the grammar, and in his wide allegorizing, but of Origenistic heresies the traces in extant works are slight. He seems to have held the preexistence of the soul. The doctrine of the “restitution of all things” is attributed to him by St. Jerome; but he speaks very often of eternal punishment, though he seems to teach that the fallen angels and even Satan himself are saved by Christ. He is fond of explaining that God‘s punishments are remedial. He deliberately rejects some of Origen’s views, and in his Trinitarian and Christological teaching is wholly uninfluenced by his great predecessor. The style of Didymus is poor and careless. He is gentle in controversy. His earnestness and piety sometimes supply the place of the eloquence and energy which he lacks.