The painting was originally meant to be part of a polyptic,
The man depicted wasn't very old but had a mental disturbance that made him unable to lead a life on his own. His cap in the drawing reminded me of the Dome of Florence, and thus, the idea of making him into a Pope came about. Being such a kind, humble, ingenious, smiling person, almost like a child, it seemed proper to manifest this innocence as opposed to popes in the past. Also, there are hints of a gayish personality.
