The parable is taken from the Decameron, and appears in several other works, but I'm not sure if any contemporary writers use this theme...besides Whittemore of course. The notion of religious tolerance looms largely in the Quartet. The Sinai Bible sort of serves as the true and original ring. I love too that the authors were a blind man and a scribe, which gives EW a kind of Homeric quality. I wonder if at any point EW himself had studied or read for pleasure these works. Any thoughts?