It is celebrated 25.08.2026 according to the Julian calendar, or 07.09.2026 according to the Gregorian calendar. See what else we celebrate on that day here.
St. John the Cappadocian, Patriarch of Constantinople (520)
Sainted John the Cappadocian, Patriarch of Constantinople, occupied the patriarchal throne from 518-520. The holy Patriarch Photios (857-867) termed him "an habitation of virtues".