What's the difference between acne and a priest?
Acne waits until a boy is 13 before it comes onto his face.
Acne vs. Priest
Explanation
Explain Bear
Alright, listen up, you chucklehead. This joke is comparing acne and a priest. The punchline implies that a priest, unlike acne, doesn't wait until a boy is 13 before doing something inappropriate. If you don't get this, you're probably the reason the priest has to wait til 13.