Musnad Ahmad 30:2122

Khalaf ibn al-Walid narrated to us, he said: al-Mubarak narrated to us, he said: Abd al-Wahid ibn Sabrah and Abbad ibn Mansur narrated to us, that they heard al-Qasim ibn Muhammad saying: I heard Abu Hurayrah saying: The Messenger of Allah, peace and blessings of Allah be upon him, said: "Indeed, Allah, the Almighty and Majestic, accepts charity, and He does not accept from it except that which is pure. He accepts it with His Right Hand, Blessed and Exalted is He, and He nurtures it for His Muslim servant just as one of you nurtures his foal or his young camel, until it arrives on the Day of Resurrection like Mount Uhud."