A nun gets into a cab, and the cab driver won't stop staring at her.
Finally, the cabbie says, "I have a question to ask you, but I don't want to offend you."
"My dear son, you cannot offend me. When you're as old as I am, you get a chance to see and hear just about everything."
"Well, I've always had a fantasy about a nun performing oral sex on me."
"Well, first, you have to be single, and then you must also be Catholic."
The cab driver says, "Yes, I am single, and I'm Catholic, too!"
The nun says, "OK, pull into the next alley." He does, and the nun fulfills his fantasy.
When they get back on the road, the cab driver starts weeping.
"My dear child, why are you crying?"
"Forgive me, sister, but I have sinned. I lied. I must confess -- I'm married and I'm Jewish."
"That's OK," says the nun. "My name is Kevin, and I'm on my way to a Halloween party."