Abu Dawud
General Behavior
Book Number: 036 / Hadith Number: 4946
Narated By A man : AbulMalih reported on the authority of a man: I was riding on a mount behind the Prophet (pbuh). It stumbled. Thereupon I said: May the devil parish! He said: Do not say: May the devil perish! for if you say that, he will swell so much so that he will be like a house, and say: By my power. But say: In the name of Allah; for when you say that, he will diminish so much so that he will be like a fly.