Abu Dawud
Wages
Book Number: 017 / Hadith Number: 3533
Narated By Abdullah ibn Amr ibn al-'As : The Prophet (pbuh) said: The similitude of the one who takes back what he gifted is like that of a dog which vomits and then it eats vomit. When a donor seeks to take back (his gift), it should be made known and he informed why he sought to take it back. Then whatever he donated should be returned to him.