No matter what her husband did in bed, a woman never achieved an orgasm. Since, by Jewish law, a wife is entitled to sexual satisfaction, they decided to consult their Rabbi.
The Rabbi listened to their story, stroked his beard, and made the following suggestion: "Hire a strapping young man. While the two of you are making love, have the young man wave a towel over you. That will help your wife fantasize and should bring on an orgasm."
They went home and followed the Rabbi's advice. They hired a handsome young man and had him wave a towel over them as they made love. It didn't help -- the wife was still unsatisfied.
Perplexed, they went back to the Rabbi.
"Okay," he said to the husband, "Try reversing it. Have the young man make love to your wife and you wave the towel over them."
Once again, they followed the Rabbi's advice. They went home and hired the same strapping young man. The young man got into bed with the wife and the husband waved the towel. The young man went about his task with great enthusiasm and soon the wife had an enormous, room-shaking, ear-splitting, screaming orgasm. The husband smiled, looked at the young man and said, triumphantly,
"See that, you schmuck? THAT'S how you wave a towel!"
P. - S. Feels like all jokes have already been told: searching the thread, I found orlok's original version but being 2½ years later I thought this variant, could still bring a renewed smile.