The Wedding Feast of the Lamb
St. Mark's Basilica, Venice
The Latin phrase above the figures is BEATI QUI AD CÆNAM NUPTIARUM AGNI VOCATI SVNT, "Blessed are they that are called to the marriage supper of the Lamb" (Revelation 19:9).
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More of the Lamb of God symbol
Photographed at the site by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.