Saint Paul is shown with his usual attributes, a book and a sword (in the lower left-hand corner). The artist made an etching of this composition which identified the figure as Saint Paul on a cartellino (a painted imitation of a small piece of paper) attached to the step. The status of the painting is unclear but it is probably a copy after the etching. However, it has also been claimed as the original on which the etching is based.
The National Gallery, Trafalgar Square, London WC2N 5DN