Note: Read this joke with an Irish accent.
A man walks up to the doorway of a pub, when suddenly a nun steps in his way.
"Sir, be off with you, now. Drinking of the demon rum is the surest way to hell. It will put all kinds of evil thoughts into your head, and turn from the rightous path!"
The man is quizzical, so he asks, "Sister, have you ever actually had a taste of fine, Irish whiskey?"
"No, I have never had a sip of the demon spirit, sir."
"Well then, Sister. How can you condem something you've never tried?"
The nun pauses for a bit, and then conceeds, "Well, sir, perhaps you're right. Perhaps you could bring me out a wee dram so I can see for meself. But if you could sir, please bring it out in a teacup, so as to maintain propriety?"
The man agrees and enters the pub, whereupon he asks the bartender for a shot of whiskey. "But if you could barkeep, pour it into a teacup, please?"
The bartender explodes, "Jay-sus, Joseph, and Mary! It's that bloody nun again!"