No topic is more fraught in American life than the relationship between religion and politics. Someone’s understanding of the American experiment often hinges upon their understanding of how the two relate: Is America a mostly secular nation that should eschew religious influence? Or, does religion play an important role in America’s legacy in terms of its values and national identity? 

Religion and public argument

Thinkers such as President John Adams and philosopher Alexis De Tocqueville both argued that religion is central to the American experiment of ordered liberty. But that raises the question of how religion is to function. We believe there are two primary ways: (1) Religion provides a system of morality necessary to teach virtue and restrain vice among its people, making self-government possible; (2) Religion provides a metaphysical account of moral norms that government looks to in order to make sense of its authority, purpose, and obligations. Hence, you have the language of the Declaration of Independence speaking of mankind’s “unalienable rights” being “endowed by their Creator.” Religion plays a vital role in making sense of the political community we live in, the values we hold dear, and the type of society and culture we hope to foster.

But this raises an important question: How should religion function in a public argument? Does a Christian legislator have the grounds to argue for a policy by citing a Bible verse? Properly understood, yes. But behind this question is the issue of authority. Considering that America does not have an established religion, it means there is a range of competing authorities to determine what moral norms are binding to policymaking. This is why theologian Jonathan Leeman refers to the public square as a “battleground of gods.” Christians do not accept the dictates of Islam, and Muslims do not believe in Christian Scripture. Moreover, we do not want laws enforced that are intelligible to or agreed upon only by members of one religion. Law is meant to advance a rational purpose and conform actions to its standards for all. So how can religion play an important part in shaping public debate if Americans have differing accounts of how moral authority originates when it comes to law and policy?

Religion and reason

In 2015, political philosopher Matthew Franck wrote an essay helping readers understand the steps one must take in translating their religious arguments to secular audiences. Franck argues positively for the rights and abilities of people—even public officials—to make religious arguments when advocating for a specific policy. To do so, he argues, religious adherents need to explain how their religiously-informed ethics relates not only to morality, but policy as well. Franck writes,

“There is no compelling reason in principle for religious citizens to refrain from employing religious discourse in the public square. They must, of course, reason together with their fellow citizens in order to persuade others of their policy views. But if their major premises, so to speak, are theological, there is no harm done, so long as their policy conclusions can be reasonably embraced by others who have different commitments.

The attribution of a “strictly religious” motivation to a policy view offers an incomplete account of how people actually reason in political life. Beliefs that may be called “strictly” religious or theological typically supply only a major premise for a policy conclusion. The minor premise will usually be supplied by other considerations—of cost, of prudence or practicality, of justice to others, of forbearance toward those same others. Even “thou shalt not kill,” for instance, is not a principle that by itself can lead straight to anything in public policy—not even a coherent homicide law—without intervening minor premises that will tell us when, how, and with regard to whom the principle will be applied.”

Let’s give a further explanation of Franck’s argument. According to Franck, the blunt use of religion to bring about a specific policy in itself is not immediately intelligible because, in a diverse country like America, it is more than possible, even likely, that someone will disagree with your account of who God is and how God has been revealed. But different understandings of who God is do not prohibit overt references to religion; rather, as Franck argues, this merely reveals the need for an act of translation to occur.

He uses the Sixth Commandment as an example. The Sixth Commandment (Ex. 20:13), in Christian moral thought, prohibits not only murder but also commands Christians to act in ways that prosper and protect life. The idea that life is worth preserving and safeguarding, to such a degree that prohibiting murder and establishing penalties for murder seems, on the surface, intelligible and rational. It may not be provable, but human experience would suggest that acting in such ways to foster life, rather than harm life, is praiseworthy. Not all moral principles are provable since they are underived and self-evident. To stay with this example, one need not be a Christian to understand that murder is wrong (Rom. 2:14-15). 

What the Sixth Commandment teaches in the broadest possible application is that we should act in ways and codify laws that reflect a fundamental good of human nature: It is better to live than to be dead. So a moral principle is on the immediate horizon, followed second by application to a particular law or policy enacted to uphold the principle. The moral principle is: Life is good, so act in ways that cause people to flourish. But, if we want to move from moral principle to public policy, we must decipher how moral abstractions can become particularized in law. This process is why, in American contexts, we have legal distinctions between first-degree murder, second-degree murder, and manslaughter. Law is deduced and specified based on the underlying moral principle. What this means is that simply saying “The Sixth Commandment should be a law” gives minimal specificity as to how to apply the underlying moral principle in particular cases. We would need to utilize wisdom and prudence to apply the broad principle of the Sixth Commandment in specific cases.

We could repeat this logic for innumerable policy considerations: Property law, contract law, family law, and political authority among them. When we talk about the application of religion to politics, it does not mean that laws on marriage, for example, are designed with the intention to explicitly honor Genesis 1-2 because everyone in America accepts Genesis 1-2 as authoritative. That surely is not the case given the diversity of perspectives in America. But from the interior perspective of Christianity, when a nation’s laws get marriage right, we say so because Christians believe that the picture of marriage in Genesis 1-2 is creational. We believe that principles of natural law, derived from and compatible with, the Christian moral tradition, are relevant to all political communities and are essential properties for the just ordering of society and the common good.

Binding moral principles

The idea of natural law ethics is that there are binding moral principles, governed by reason and attested to in nature, that all persons, regardless of whether they are Christians or not, are obligated to obey for their own sake and God’s. Marriage in Scripture bears witness to a creational reality. And that’s the context where most discussions of how Christians relate to the political sphere begin: The portrait of reality given in creation is not “Christian reality,” but reality as it truly is. 

Thus, when Christians insist on laws upholding the dignity of the unborn or seeking justice for victims of sex-trafficking, we do so because concepts like dignity reflect a principle of morality that is binding on all persons. Christians believe this is true regardless of whether a person accepts the specific teaching that humans are made in God’s image. Every person possesses innate dignity and should have that dignity recognized and protected in the law. Someone will agree with this by appeal to revelation, or they will assert the same idea on other grounds, or they will reject the idea altogether. This is because the existence of human dignity is either true for all or false for everyone. Furthermore, because we believe that God’s common grace gives all persons an ineradicable sense of right and wrong, we believe that society can attain a reasonable morality to allow for its continued existence.

Public policy, from the perspective of Christian thought, incorporates themes of Christian ethics at the broadest possible level. To say that Christians should care about public policy and make arguments as Christians in the public square is not to say that Levitical laws on sacrifices or Deuteronomic civil law are going to make their way into federal statute. Nor should they, as Levitical laws foreshadow Christ and Deuteronomic laws dissolved with the passing of the Israelite theocracy. No, only those moral principles of broadest application to the public square are relevant to public policy, and then particularized to meet the needs of those living within a political community. It means we have a duty to explain and articulate the inner-workings of Christian moral thought and how they relate to an issue of public significance.

So do not be fooled. Banal, oft-quoted statements such as “you cannot legislate morality” are coined phrases meant to intimidate religious persons while smuggling in non-neutral secular morality. Far from being “neutral,” such an argument unfairly tilts public discourse in the direction of the non-believer, which violates the spirit of the First Amendment. The secularist and religious believer have just as much say in making their arguments in the public square. Those with the best, most persuasive arguments deserve to win out on matters of public concern.