Continuity mistake: When the Fighting Temptations are performing at the Gospel choir contest at the end, the convict with the high voice is dancing with only one handcuff attached (you can see him try to hide the other end, which is flapping around). In a subsequent shot, he has both handcuffs attached again.
Continuity mistake: When the lady he is staying with is telling the choir that he is in advertising, and the other lies he had been telling everyone, one lady says, "and i was going to sleep with you.". And the lady and the whole church made a big deal about Lily having sex without marriage, but this would be sex without marriage too, and everyone just gives her a weird look. At least the lady would have said something to her.