In Florence the natal day Not his birthday but the day he died and was "born again" into Heaven of St. Zenobius, bishop of that city. He was conspicuous for his sanctity and the glory of his miracles. – Roman Martyrology for May 25
St. Zenobius was Bishop of Florence in the 4th century. He is first mentioned in Paulinus of Milan's Life of St. Ambrose in 422, where he is said to have had a vision of Ambrose in a Florentine house that had been visited by that saint while he was alive. However, it was not until the 11th century that vitae began to appear celebrating Zenobius's life and miracles, and these made him a friend and contemporary of Ambrose.
The vitae recount a number of miracles performed by Zenobius during his lifetime, and these were portrayed in many paintings sponsored by the cathedral chapter in Florence and various churches there. (See examples by Botticelli and Gozzoli).
Portraits of St. Zenobius show him as at right in episcopal regalia. The portraits vary widely regarding the saint's appearance but many show him with a white beard, sometimes short and square as at left. Thus he has to be identified by context. Some pictures will show him with what appear to be two deacon saints wearing dalmatics. These are St. Eugenius his archdeacon (seated on the right in the picture) and the subdeacon St. Crescentius. A painting in the Cathedral Museum in Florence puts him in the context of the other two saints most associated with that city, Reparata and John the Baptist.
Prepared in 2015 by Richard Stracke, Emeritus Professor of English, Augusta University