From Albert M. Wolters' Creation Regained:

There is . . . a crucial difference between the laws of nature and norms. In speaking of the "stormy winds that do his bidding" (Ps. 148:8), the psalmist does not ascribe responsibility to the wind. The wind cannot help but obey. But human beings do have responsibility: we are held to account for the way we execute God's commandments, and we are liable to punishment if we do not execute them all. Norms are complex. They can be violated in any number of ways, and they also leave a good deal to the resourcefulness and responsible imagination of the human being who is called to implement them. The command "Be just" must be applied to many different and complex human situations, nor is it always easy to determine in any given situation what justice requires. Yet it is our uniquely human task to put into concrete practice the requirements of the norm for justice. A falling stone has no comparable task in obeying the law of gravity, nor does an eagle in observing God's ordinances for raising its young. The stone obeys necessarily, the eagle responds instinctively, but a person must exercise personal responsibility: we are called to positivize the norm, to apply it to specific situations in our lives. All of human life, in all its vast array of cultural, societal, and personal relationships, is normed in this sense. The almighty Creator lays claim to all; the universal Sovereign lays down his laws for it all; the absolute King requires his will to be discerned in it all.