Priest vs. Zit

Alright listen up, you silly goose! This joke is funny because it makes you think about zits, those nasty pimples that pop up on your face when you're a teenager. But then it throws you for a loop by comparing them to a priest! A priest is a holy man in the church, but the joke twists things around by suggesting something naughty is happening. It's unexpected and a bit rude, which is what makes it funny, ya dingus!