Saint Proclus (d. July 446) was a patriarch of Constantinople.

The friend and disciple of John Chrysostom, he became secretary to Patriarch Atticus of Constantinople. who ordained him deacon and priest. Sisinnius, the successor of Atticus, consecrated him bishop of Cyzicus but the people there refused to receive him, and he remained at Constantinople. On the death of Sisinnius, the famous Nestorius succeeded, and early in 429, on a festival of Virgin Mary, Proclus preached the celebrated sermon on the Incarnation inserted in the beginning of the Acts of the council of Ephesus.

When Maximianus died on the Thursday before Easter in 434, Proclus was immediately enthroned by the permission of Theodosius and the bishops at Constantinople. His first care was the funeral of his predecessor, and he then sent both to Cyril and John of Antioch the usual synodical letters announcing his appointment, both of whom approved of it.

In 436 the bishops of Armenia consulted him upon certain doctrines prevalent in their country and attributed to Theodore of Mopsuestia, asking for their condemnation. Proclus replied next year in the celebrated letter known as the Tome of Proclus, which he sent to the Eastern bishops asking them to sign it and to join in condemning the doctrines arraigned by the Armenians. They approved of the letters, but from admiration of Theodore hesitated to condemn the doctrines attributed to him. Proclus replied that while he desired the extracts subjoined to his Tome to be condemned, he had not attributed them to Theodore or any individual, not desiring the condemnation of any person. A rescript from Theodosius procured by Proclus, declaring his wish that all should live in peace and that no imputation should be made against anyone who died in communion with the church, appeased the storm. The whole affair showed conspicuously the moderation and tact of Proclus. In 438 he transported to Constantinople from Comana, and interred with great honour in the church of the Apostles, the remains of his old master Saint John Chrysostom, and thereby reconciled to the church his adherents who had separated in consequence of his condemnation.

In 439 at the request of a deputation from Caesarea in Cappadocia, he selected as their new bishop Thalassius, who was about to be appointed pretorian prefect of the East.

In the time of Proclus the Trisagion came into use. The occasion is said to have been a time when violent earthquakes lasted for four months at Constantinople, so that the people were obliged to leave the city and encamp in the fields.

Proclus died most probably in July 446. He appears to have been wise, moderate, and conciliatory, desirous, while strictly adhering to orthodoxy himself, to win over those who differed from him by persuasion rather than force.

His works (Migne, Patr. Gk. lxv. 651) consist of 20 sermons (some of doubtful authenticity), 5 more published by Card. Mai (Spic. Rom. iv. xliii. lxxviii.), of which 3 are preserved only in a Syriac version, the Greek being lost; 7 letters, along with several addressed to him by other persons; and a few fragments of other letters and sermons. Socrates. H. E. vii. xxvi., and passim; Theophanes A.D. 430; Tillem. Mém. eccl. xiv. 704; AA. SS. Act. x. 639.

This article uses text from A Dictionary of Christian Biography and Literature to the End of the Sixth Century A.D., with an Account of the Principal Sects and Heresies (http://www.ccel.org/w/wace/biodict/htm/TOC.htm) by Henry Wace. [1] (http://www.ccel.org/w/wace/biodict/htm/iii.xvi.cv.htm#iii.xvi.cv)