Nakdimon ben Guryon borrowed water for the numerous pilgrims who had ascended to Jerusalem. Just before the repayment deadline his prayers were answered, and in a short while rain filled the many cisterns, repaying his debt. The sun then reemerged from behind the clouds on his behalf.

The Sages taught: One time all the Jewish people ascended for the pilgrimage festival to Jerusalem, and they did not have enough water to drink. Nakdimon ben Guryon went to a certain gentile official and said to him: Lend me twelve cisterns of water for the pilgrims, and I will give you twelve wells of water in return. If I do not give them to you, I will give you twelve talents of silver. The official agreed, and fixed a time limit for him to return the water.

When that time arrived and no rain had fallen, in the morning, the official sent a message to Nakdimon: Send me either the water or the money that you owe me. Nakdimon sent to him: I still have time, as the entire day is mine. [The deadline is at the end of the day.] At noon the official sent the same message to him: Send me either the water or the money that you owe me. Nakdimon sent the same message back to him: I still have time left in the day. In the afternoon, he sent the same message to him: Send me either the water or the money that you owe me. Nakdimon sent the same message back to him: I still have time left in the day. That official ridiculed him, and said: Rain did not fall throughout the entire year, and now rain will fall?

The official entered the bathhouse joyfully. As this master was joyfully entering the bathhouse, Nakdimon entered the Temple sadly. He wrapped himself in his prayer shawl and stood in prayer.

He said before God: Master of the Universe, it is revealed and known before You that I acted neither for my honor, nor for the honor of the house of my father; rather, it was for Your honor that I acted, so that there would be water for the pilgrims. Immediately the sky became overcast, and rain fell until the twelve cisterns were filled with water, beyond what they had been originally.

As the official left the bathhouse, Nakdimon ben Guryon left the Temple. When they encountered one another, Nakdimon said to him: Give me the money you owe me for the surplus water you received. The official said to him: I know that the Holy One, blessed be He, has brought upheaval to His world and caused rain to fall now only on your behalf. But I still have a claim against you, through which I can collect my money from you, as the sun had already set, and the rain that fell after the deadline had already passed was in my possession.

Nakdimon went back and entered the Temple, wrapped himself in his prayer shawl, and stood in prayer. He said before God: Master of the Universe, let it be known that You have beloved ones in Your world. Immediately, the clouds scattered and the sun shone. At that moment, the official said to him: Had the sun not broken through the clouds, I would have had a claim against you, which would have allowed me to collect my money from you. The Sages taught: Nakdimon was not his real name; rather his name was Buni. Why was he called Nakdimon? It is because the sun broke through [nikdera] for him. (Ta’anit 19b–20a)