Tribute, Spoils, and Rulership (Kitab Al-Kharaj, Wal-Fai' Wal-Imarah)
Dawud :: Book 19 : Hadith 2941
Narrated AbuMas'ud al-Ansari:
The Prophet (peace_be_upon_him) appointed me to collect sadaqah and then said: Go, AbuMas'ud, I should not find you on the Day of Judgment carrying a camel of sadaqah on your back, which rumbles, the one you have taken by unfaithful dealing in sadaqah. He said: If it is so, I will not go. He said: Then I do not force you.