Musnad Ahmad 30:623

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from Ayyub, from Ibn Sirin, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The best charity is that which is given from surplus wealth, and begin with those whom you support, and the upper hand is better than the lower hand." I said to Ayyub: "What is 'from surplus wealth'?" He said: "From the excess of your wealth."