A Rabbi and a Priest were sitting in front of a church and they each had charity boxes in front of them to collect money.
The church goers that were passing by couldn’t believe the nerve of the rabbi, and purposely threw large sums of money into the priest’s charity box to spite the rabbi. Finally one of the passers-by had sympathy for the rabbi, and advised him, “Go to a synagogue and collect there, you’ll have more success. “
The Rabbi thanked the passer-by, and then turned to the priest and said, “You hear that, Yankel; he’s telling us how to do business. “
This joke is included in the Black Book of Jokes. You can order it from here.