Rear of the Apse of the Euphrasian Basilica, Poreč, Croatia
The censer is St. Zacharias' attribute in portraits. His vestments resemble those of 6th-century bishops, to reference his role as a Temple priest. The box in his hand may refer to the Temple itself or to the Ark of the Covenant.
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Photographed at the site by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.