St John the Evangelist
Church of Santa Maria dell'Ammiraglio ("The Martorana")
The church was founded by a Greek official in the court of Roger II and was in use by the Greek Orthodox community in Palermo for several centuries.
The saint sits beside a bookstand and writes in a book. The book is most likely his gospel, the opening phrase of which is inscribed in the banderole that surrounds the image: "In the beginning was the Word, and the Word was with God." The smaller inscription inside the banderole means "St. John the Theologian."
Western images often make John a young man without a beard, even when he is shown in what would have to be his later life. But it is traditional in Orthodox images such as this one to give him gray hair and beard.
This image in full resolution
More of St. John the Evangelist
Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.