Traditio Legis Fragment

4th century?
Museum of the Church of St. Paul Outside the Walls, Rome

Possibly the relief is a Traditio Legis, the iconographic type in which Christ hands keys to St. Peter and a book or scroll to St. Paul. The short, square beard of the man at Christ's left may identify him as Peter. He receives a scroll and holds something in his left hand that could be a fragment of a cross or a set of very large keys. The man to the Christ's right holding a rolled-up scroll could thus be St. Paul.

Directly left of Christ's right leg is an animal with horns or antlers that have been broken. If antlers, the reference may be to Psalm 41:2, "As the hart panteth after the fountains of water; so my soul panteth after thee, O God." The small hill on which Christ stands is incised to suggest water flowing down, a not uncommon motif in paleo-Christian art (example).

Two smaller animals right and left of the center columns look like dogs but may be smaller harts.

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Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.