Hierarch Memnon of Ephesus

IMPORTANT NOTE: no standing independent commemoration of this hierarch was found on the Russian Orthodox calendar — the date given (December 16/29) is attested in the Greek Synaxaristes but does not appear on azbyka.ru or in the Orthodox Encyclopedia as an independent feast; noted as Greek tradition rather than general church practice. Almost nothing is known of his life apart from his conciliar activity — neither his birthplace and year nor his exact date of death survive in any source.

Hierarch Memnon was metropolitan (archbishop) of Ephesus at the time of the Third Ecumenical Council (431), which he hosted in his own city. Together with St. Cyril of Alexandria, he was one of the council's principal organizers and led the majority that opened proceedings before John of Antioch's delegation had arrived — a procedural decision that became a major point of contention.

Memnon closed the Ephesian churches to Nestorius's supporters; when John of Antioch arrived and convened a parallel, unauthorized council of about 43 bishops that "condemned" both Cyril and Memnon, Memnon refused to grant them a church building for their sessions. At later sessions, Cyril and Memnon jointly protested John's actions and secured his excommunication. Emperor Theodosius II briefly placed all three principal figures (Cyril, Memnon, and Nestorius) under arrest, but ultimately upheld the council's decisions, restoring Cyril and Memnon and exiling Nestorius. Only one of his works survives — a letter to the Constantinopolitan clergy.

His feast is kept on December 16/29 according to Greek tradition.