Scholars of politics and law continue to debate whether liberal democracy—that form of government grounded in the consent of the governed and devoted to protecting the rights shared equally by all—is rooted in moral preconditions. Since liberal democracy obviously rests on the fundamental moral premise that all human beings are by nature free and equal, the persistence of this debate testifies to nothing so much as the ability of intellectuals to cloud almost any issue.

Liberal democracy’s fundamental moral premise does, however, generate hard questions, both of the theoretical and the practical kind.  Prominently driving the former these days are certain ideas or schools of thought fostered in our universities and disseminated throughout popular culture.  For one thing, contemporary scientism limits all knowledge to that which can be formulated in terms of matter and the laws of physical nature.  For another, postmodernism reduces all claims of knowledge, even the claims of science, to expressions of human will and social artifice.  Both schools of thought lead to the same conclusion: the very notion of universal and objective moral claims grounded in human nature is nonsensical.

As for hard practical questions, these center on whether liberal democracy’s actual beliefs, practices, and associations are consistent with its fundamental moral preconditions. And which, if any, contribute to liberal democracy’s preservation and improvement?

Rare is the scholar of politics or of law these days who would think to turn to the Ten Commandments to understand better the hard questions to which liberal democracy gives rise. But Leon Kass’s remarkable exploration of the Decalogue shows that these scholars have neglected a vital resource.

At once sympathetic and probing, Kass’s essay emphasizes the Decalogue’s universal significance without slighting its role as, specifically, a preamble to the detailed legal code that constitutes the children of Israel as a people summoned to become a kingdom of priests and a holy nation.  His engaged and respectful treatment of both the universal and the particular yields an uncommon insight.  In opposition to the widespread conceit that religious law and individual freedom are antithetical, Kass shows that the religious law embodied in the Decalogue encourages those who live under it to appreciate their right as human beings to govern themselves in freedom.

Kass places particular emphasis on the statement in the Decalogue about the Sabbath day.  Among other things, the duties imposed in this statement incorporate into the rhythms of the week actions, and the cessation of actions, that call to mind what distinguishes human beings from the rest of creation.  Central to the command to remember the Sabbath day and keep it holy is the act of desisting from work: in this, we humans are directed to imitate God, who desisted from his work of creation on the seventh day and hallowed it.  What allows us to grasp and heed this point? The fact that human beings—male and female, as Genesis 1:27 stresses—are made in the image of God.

To proclaim that human beings are created in the image of God is not to affirm, with liberal democracy, that human beings are by nature free and equal.  But it is to affirm something closely related. The God of the Hebrew Bible, who will be what He will be, whose ways are mysterious, and whose words are endlessly rich and endlessly disputable, differs from nature, which cannot be other than it is and operates according to fixed laws that can be grasped by the human mind.  Yet the biblical teaching encapsulated in the Ten Commandments is consistent with and reinforces liberal democracy’s fundamental moral premise. Both declare that human beings are in the most important respect equal; that men and women are elevated above inanimate nature and other creatures and deserving of special regard in virtue of what they share as human beings; and that they are degraded when enslaved or subjected to the arbitrary rule of other human beings.

The three prohibitions in the Decalogue that come before the command to remember the Sabbath day are also consistent with and support the claims of freedom.  The prohibitions against having other gods, making graven images or physical likenesses of God, and using God’s name in vain—each addresses an error or errors in the way human beings relate to God.  The prohibitions on committing these errors emancipate men and women from the worship of false gods and from the false worship of the one God in whose image they are formed.

These four commandments taken together, concentrating on duties to God, place the emphasis on what to believe and how to express it. The next six, focusing on duties to fellow human beings, stress daily, mundane conduct. They too are consistent with and support the claims of freedom.

Seminal thinkers in the larger liberal tradition—among them Locke, Burke, Tocqueville, and Mill—have identified the family as the bedrock association within political society, the site where the virtues of freedom are first and most decisively formed. The command to honor your father and mother, as Kass observes, is crucial to holding the family together.  Honor is distinct from love, which is subject to fortune and passion, and also from obedience, which fades as children become adults.  Instead, honor involves recognition of status or role: parents bring us into being, nurture us when we are helpless, form our character, and one day will be in need of our care as their ability to care for themselves wanes.  By delinking our obligations to our parents from, on the one hand, the vicissitudes of fortune and passion and, on the other hand, the limited period of time in which obedience is appropriate , the commandment to honor one’s parents promotes the family’s long-term integrity and stability.

The commandments against murder, adultery, stealing, and bearing false witness deliver freedom from the bondage of the worst human tendencies.  Also, by protecting life, family relations, property, and reputation and promises, these practical prohibitions promote the social coordination and competition critical to the prosperity of liberal democracy. 

The final commandment, prohibiting the coveting of that which belongs to your neighbor, departs from the other commandments in this second set by, in Kass’s words, “focusing not on an overt action but on an internal condition of the heart or soul.”  But the departure functions to reinforce the practical commandments as a whole by orienting “the heart or soul” in a manner that disposes us to avoid also the overt prohibited actions.

But wait: does not this prohibition of coveting, along with the earlier commandments involving duties toward God, infringe on basic freedoms associated with liberal democracy? What could be more illiberal than prescribing or forbidding a form of belief, or attempting to regulate the heart and soul? 

This objection misunderstands liberal democracy and the Ten Commandments alike.  Yes, liberal democracy repudiates the prescribing of belief and the regulation of the heart and soul by government. But it does not declare the content of citizens’ beliefs and the inclinations of their hearts and souls to be morally and politically irrelevant.  What is more, the behaviors and convictions set forth in the Ten Commandments are offered to the children of Israel as a choice; they become authoritative upon the free acceptance by the Israelites of the covenant with God.

Although itself a work neither of politics nor of law, Kass’s masterful interpretation of the Ten Commandments illuminates the hard questions, theoretical and practical, arising from liberal democracy.  He provides powerful reasons for believing that the Decalogue is not only consistent with but also supports human freedom.

This leaves an intriguing question that Kass’s analysis discreetly contemplates but does not decide: namely, whether the Decalogue is indispensable to the preservation and improvement of liberal democracy.  To answer that question adequately, we would need to pursue simultaneously a searching analysis of biblical faith, a rigorous investigation of the roots of liberal democracy, and a historical study of the variety of shapes liberal democracy has taken and the range of circumstances in which its principles have flourished.

For thus clarifying the task facing students of liberal democracy, and for so much else besides, we owe Leon Kass a debt of gratitude.

Peter Berkowitz is the Tad and Dianne Taube Senior Fellow at the Hoover Institution, Stanford University. He is the author of, most recently, Constitutional Conservatism: Liberty, Self-Government, and Political Moderation.