Demosthenes, i Against Meidias:

What is the strength of the laws? If one of you is wronged and cries aloud, will the laws run up and be at his side to assist him? No; they are only written texts and incapable of such action. Wherein then resides their power? In yourselves, if only you support them and make them all-powerful to help him who needs them. So the laws are strong through you and you through the laws.

HT: Tom G. Palmer