Abu Dawud
Zakat
Book Number: 003 / Hadith Number: 1645
Narated By Malik ibn Nadlah : The Prophet (pbuh) said: Hands are of three types: Allah's hand is the upper one; the bestower's hand is the one near it; the beggar's hand is the lower one. So bestow what is surplus, and do not submit yourself to the demand of your soul.