Andrea Bregno, Frontal of the Monument to Nicholas of Cusa
Church of St. Peter in Chains, Rome, Italy
The relief presents St. Peter on his throne. Many images of various periods give him the kind of curly hair and beard seen here. His left hand holds the chains from which he was freed by the angel shown at right (Acts 12:6-7). His right holds his more common attribute, the keys to the Kingdom of Heaven.
The cardinal on the left is Nicholas of Cusa, a noted Renaissance humanist and papal diplomat. Most later images of him collected at Wikimedia Commons have basically the same facial features and even the same hands clasped in prayer.
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Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.