A guy's about to walk into a bar when a nun charges up to him and screams, "Drinking alcohol is a sin! Repent or be damned to Hell!"
The guy says, "Now hold on, sister. Have you ever tried alcohol?"
"Well, no I haven't," the nun admitted.
The guy asks, "Then how do you know if it's that bad?"
"Well, I suppose I can't," the nun says, "but I can't very well take my first drink right here in plain view."
"No problem. I'll have them put it in a teacup. No one'll know. Hang on."
So the nun waits outside while the guy goes inside and calls the bartender to order two beers, one in a glass, and the other in a teacup.
The bartender says, "Oh no, it's not that nun again, is it?"