God Almighty said, “Fear God, and God will teach you.” And He said, “If you fear God, He will make for you a criterion.” And He said, “Fear God and believe in His Messenger. He will give you two guarantees of His mercy and make for you a light by which you may walk.” Give you something like his saying about his servant Khidr: We gave him mercy from Us and taught him knowledge from Us, so he made giving him knowledge his servant. Of His mercy and piety is a lawful act for us, so piety must be the relation of His ruling to one or all of these pieces of evidence in any matter in which we are required to fear God .