Thus the law of nature stands as an eternal rule to all men, legislators as well as others. The rules that they make for other mens actions, must, as well as their own and other mens actions, be conformable to the law of nature, i.e. to the will of God, of which that is a declaration, and the fundamental law of nature being the preservation of mankind, no human sanction can be good, or valid against it.
John LockeHe that judges without informing himself to the utmost that he is capable, cannot acquit himself of judging amiss
John LockeWhensoever, therefore, the legislative shall transgress this fundamental rule of society, and either by ambition, fear, folly, or corruption, endeavour to grasp themselves, or put into the hands of any other, an absolute power over the lives, liberties, and estates of the people, by this breach of trust they forfeit the power the people had put into the hands... and it devolves to the people, who have a right to resume their original liberty, and... provide for their own safety and security.
John Locke