This paper originated as an invited contribution to a symposium on "Implementing Religious Law in Contemporary Nation-States: Definitions and Challenges," sponsored by the Robbins Collection, Berkeley Hall, Boalt Hall, U.C. Berkeley, February 2014. The symposium by design brought papers speaking variously from Christian, Jewish, and Muslim perspectives into conversation. My paper proposes that the Catholic tradition of reflection on human lawmaking, even in modern nation-states, must take as its starting point the God who rules His rational creatures through higher or eternal law, where the rational creature’s participation in that higher law is what is known as the natural law. Using the writings of St. Thomas Aquinas as a foundation, it argues that the divinely ordained remedy for the breakdown of human understanding and willing of the natural law is divine positive law, both of the Old Testament and the New Testament, as interpreted by the Church. It further notes that in the United States, this remedy is denied or severely circumscribed by modern political theory and the constitutional doctrine shaped by such theory. The paper concludes then, in Part IV, by considering: (1) the implications of the fact that religion is a component of justice, not, as it is increasingly (mis-)understood, a mere act of self-assertion; (2) some of the requirements of toleration as a disposition of modern states toward their citizens and of citizens toward their fellow citizens; (3) the impossibility of truly "sovereign" states; and (4) higher law's aim to unite human persons with the Divine persons.