A man went fishing for his first time, and after two boring hours and not having catched anything starts walking the river shore back home.
After he'd walked for a couple of minutes he met this man that was also fishing, but he'd catched more than 10 fish. He asked the man, "Excuse me sir, what do you use as bait?".
"You see", the man answered, "Actually I'm a surgeon, and I save all the child tonsils I extract and later use them as bait".
The guy keeps walking back home and meets another fisher, who'd catched more than 20 fish. He asked the man the same question, and the man replied, "Actually I'm a surgeon, and I save all the moles I extract and later use them as bait".
He kept walking home, and he met a third fisher, who'd catched more than 100 fish! He incredously asked, "Doctor, what do you use as bait?" To which the man replied: "Actually, I'm a Rabbi..."