The Wedding Feast of the Lamb

Mosaic
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.