Sahih Muslim Book 020, Hadith Number 4536.
Chapter : Obedience to the ruler is forbidden in matters sinful, but is otherwise obligatory.
It has been narrated on the authority of 'All who said: The Messenger of Allah (may peace be upon him) sent an expedition and appointed over the Mujahids a man from the Ansar. (While making the appointment), he ordered that his work should be listened to and obeyed. They made him angry in a matter. He said: Collect for me dry wood. They collected it for him. Then he said: Kindle a fire. They kindled (the fire). Then he said: Didn't the Messenger of Allah (may peace be upon him) order you to listen to me and obey (my orders)? They said: Yes. He said: Enter the fire. The narrator says: (At this), they began to look at one another and said: We fled from the fire to (find refuge with) the Messenger of Allah (may peace be upon him) (and now you order us to enter it). They stood quiet until his anger cooled down and the fire went out. When they returned, they related the incident to the Messenger of Allah (may peace be upon him). He said: If they had entered it, they would not have come out. Obedience (to the commander) is obligatory only in what is good.