Narrated Ibn ‘Umar:
Umar got some property in Khaibar and he came to the Prophet and informed him about it. The Prophet said to him, “If you wish you can give it in charity.” So ‘Umar gave it in charity (i.e. as an endowment) the yield of which was to be used for the good of the poor, the needy, the kinsmen and the guests.
Sahih Bukhari, Volume 4, Book51, Number 34