Abu Huraira reported
While a person was in the wilderness he heard a voice from the cloud (commanding it thus): Irrigate the garden of so and so. (After that the clouds slinked aside and poured water on a stony ground. It filled a channel amongst the channels of that land and that person followed that water and he found a person standing in the garden busy in changing the course of water with the help of a hatchet. He said to him: Servant of Allah, what is your name? he said: So and so. And it was that very name which he had heard from the clouds. and he said to him: Servant of Allah, why do you ask me my name? He said: I heard a voice from the clouds of which is the downpour, saying: Water the garden of so and so, like your name. What do you do (for the favour) shown to you by Allah in this matter? He said: Now as you state so. I look what yield I get from it, and I give one-third as charity out of it and I and my children eat one-third of it and one-third I return to it as investment.
This hadith has been narrated on the authority of Wahb b. Kaisan with the same chain of transmitters but with this change that he said
" I earmark one-third for the poor, the needy and the wayfarers."