St. Stephen's Vision of the Son of God
Church of San Moisè, Venice, Italy
Actually, Stephen's vision of "the heavens opened, and the Son of man standing on the right hand of God" (Acts 7:56) occurs before the mob drags him out of the city and stones him to death. The artist has collapsed the two events so that the "Son of man" can be shown handing down a palm branch in recognition of the martyr's victory.
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Source: Photographed at the site by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.