Choni HaMe'agel lived during the Second Temple period. Once the people turned to Choni HaMe'agel and asked him to pray for rain. He prayed, but no rain fell. What did he do? He drew a circle and stood within it and called out, "Master of the Universe, Your children have turned to me because I am like a member of your household. I swear by Your great name that I will not move from here until You have mercy upon Your children."
A light rain began to fall. He said, "It is not for this that I have asked, but for rain to fill cisterns, ditches, and pools." The rain began to come down forcefully. He said, "It is not for this that I have asked, but for rain of favor, blessing, and bounty." The rain then fell in the normal way.
It rained so much that everybody in Yerushalayim went to the Temple Mount to escape the flooding. They told Choni HaMe'agel, "Just as you prayed for the rain to fall, pray for the rain to leave." The Nassi, Shimon ben Shetach, sent a message to Choni, saying, "Were it not that you are Choni I would have decreed upon you nidui [a ban; excommunication; because he troubled the All-Present about the rain so many times (see Rashi on Berachot. 19a)]. But shall I do to you? You importune God and He accedes to your request like a son who importune his father and he accedes to his request..." The rain fell on the 20th of Adar after 3 years of drought and famine, and it became a day of rejoicing (Mishnah Taanit 2:10-12, 66d).