CYRIL, Sr, patriarch of Alexandria, was educated under his uncle Theophilus, the bishop of that place, and spent a considerable part of his youth in the adjacent monasteries of Nitria. From this solitude, however, he was recalled by his uncle, who installed him as preacher in the cathedral, and instilled into his mind those lessons of zeal and dominion which the unscrupulous antagonist of Chrysostom was so well qualified to impart. On the death of Theophilus the clergy were divided in their choice of a successor; but a restless multitude asserted the cause of their favourite archdeacon, and the ambitious Cyril was duly installed in the throne of Athanasius. Like Nestorius, the contemporary bishop of Constantinople, he began his patriarchal reign with a vigorous persecution of heretics; and the first victims were the Novatians, the most innocent of all the existing sects. His next stroke was aimed at the Jews, whom he attacked at the head of a seditious multitude, and levelled their synagogues with the ground. Hypatia, the daughter of Theon the mathematician, was the next to excite his jealousy; and having been represented as alienating the mind of the governor from the clergy, she was dragged to the church and murdered by a band of merciless fanatics. (See HYPATIA.) One step only remained to gratify his ambition; and the phraseology of Nestorius (acquired in the Syrian school) in regard to the two natures of Christ, afforded an admirable opportunity for the degradation of the Byzantine pontiff. After a short correspondence, the patriarch of Alexandria denounced to the emperor the heresy of Nestorius, and carried his plea to the Vatican. Pope Celestine, ignorant of Greek, and therefore incapable of realizing the defence of the accused, hastily assembled a council, which condemned Nestorius and degraded him from his rank. From Rome the contest travelled back to Ephesus, and there the arrival of the Eastern bishops under John of Antioch converted the ecclesiastical quarrel into a warlike feud. The intrigues of Cyril, however, triumphed over every obstacle; and after an appeal to Theodosius the emperor, the belligerents, partially reconciled, concurred in the condemnation of Nestorius. On returning to Alexandria, Cyril was engaged in a controversy with Theodoret, which lasted till his death, A.D. 444. The principal works of Cyril are his Glaphyra, or commentaries, and a variety of controversial treatises and epistles. The former are disfigured by a constant rage for allegorizing; and the latter, besides the obscurity arising from the abstruse nature of their subjects, are involved in additional uncertainty by the ruggedness and obscurity of his style.