St. John Chrysostom
Byzantine, 12th century
Painted on wall, modern restoration
The museum's label identifies this only tentatively as John Chrysostom. There is no attribute or inscription. However, as the label points out and an examination of the Chrysostom portraits at Wikimedia Commons makes clear, this saint "is usually depicted with a pointed beard, sunken cheeks, and a high forehead." He is most often, but by no means always, portrayed with a full head of hair.
Photographed at the museum by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.