Did Hopkins and Demme purposefully include allusions to Mantegna's paintings of St. Sebastian in Silence of the Lambs? It seems so obvious to me but I can find no reference to it online. I would like to know the reasons why. There is a clear reference in the Hannibal TV series and of course many references to Hannibal's affinity for art.
I'm not sure what moments you are referencing in Silence of the Lambs, but in the book Red Dragon the victim that leads Will Graham to realize Hannibal is a murderer was found “laced to a pegboard where the [woodworking] tools hung, and he was really torn up, cut and stabbed, and he had arrows in him.” This display of the body vaguely reminded Will of something-- that something has been interpreted by the TV show Hannibal to be "The Wound Man", but the mentions of arrows in the book is more similar to St. Sebastian.
Thus, any allusions to St. Sebastian in the film Silence of the Lambs are probably references to the way in which Hannibal was apprehended in the books.
The Wound Man: