A priest offers to show a pretty young nun the "key to the kingdom of heaven" and seduces her with it. She innocently tells the mother superior, who says, "Why that lying son of Satan; for twenty years he's been telling me it was Gabriel's horn, and I've been blowing it!" (Calif. 1952) This story is of Italian-American provenance, and is unquestionably connected with the folktale motif K1315.1.1, "Seduction by posing as the Angel Gabriel," which Rotunda cites from Bocaccio IV.2, and other novellieri, with further references to Lee and Di Francia on Boccacio's sources. (Motif-Index of the Italian Novella in Prose, 1942, p.102)
G. Legman, Rationale of The Dirty Joke, 8. MARRIAGE V. Oragenitalism 1. FELLATION BY THE BRIDE
Leg man, eh?