Continuity mistake: At the end of the scene when Homer first goes to Juan's diner, the amount of orange juice in Homer's glass changes when he and Juan introduce themselves.
Continuity mistake: In the scene where Sidney Poitier is sitting down to supper with the nuns there is a full plate of bread. He takes a piece off the full plate and the camera cuts to the mother superior. The plate is now empty. The camera cuts back to Sydney Poitier and the plate is full of bread. During the conversation all of the nuns are sitting down, none get up to refill the plate.
Audio problem: In the scene where Homer teaches the Nuns to sing the hymn "Amen", it is quite obvious that Sidney Poitier's voice has been dubbed by another singer.