As told by my father
The famous Rabbi came to the village on his coach. Everyone was already waiting for him, the rumor had been spread that the Rabbi got a Question and that there was also a prize for whoever would solve it – marrying the Rabbi’s daughter.
All the brilliant sages sharpened their mind and polished their memory, eager to demonstrate their wit, to excel before the Rabbi.
The Rabbi arrived, and the Question was asked.
Two days passed and no one came forth with a successful answer.
The Rabbi left the village.
A young man ran after the Rabbi’s coach. “Rabbi!”, shouted the young man, “Rabbi, please wait”. The Rabbi signaled to the coachman, and the coach halted.
“What is it young man?” asked the Rabbi. “Do you know the answer?”
“No, no”, said the young man, “but please Rabbi, tell it to me, let me know the answer. The Question is so… wonderful”.
The Rabbi smiled at the boy. “Come on”, he said, “get into the coach”.
[ and compare with If you can say it, I will open the door]