Psalms 119:4

Thou hast commanded -All this is here traced to the command of God; to the fact that he has required it. It is not mere human prudence; it is not mere morality; it is not because it will be for our interest; it is because God requires it. This is the foundation of all true virtue; and until a man acts from this motive it cannot be said that he is in the proper sense a righteous man. To keep thy precepts diligently -Hebrew, “very much;” that is, to do it constantly; faithfully. Each one of his laws is to be observed, and to be observed always, and in all circumstances.