Imagine this scenario: A Christian is discussing abortion with their secular, unbelieving friend. Sensing that they are at an impasse, the Christian says, “The Bible says murdering a human being is wrong.” His friend replies, “I do not believe the Bible.”
Was the Christian wrong to assert a Biblical truth? By no means. But was he making an argument that his friend could dismiss because he rejects the inspiration of the Bible? Yes. A faithful response is not the same thing as an effective or persuasive response in every context.
The Christian was not making a problematic conclusion. No, the problem was a category confusion—he failed to distinguish the source of morality from its content. While the Christian knows that God is the author of the moral law, that does not settle the separate question of whether the claim that abortion constitutes the murder of a human being is intelligible on its own terms. And indeed, it is intelligible on its own terms—an intelligibility that is reasonable and publicly accessible, and which corresponds to the types of creatures we are. Murder is wrong because unjust killing is always wrong. Why? Because it corresponds to the mind’s fittedness to grasp moral truth.
I offer the example above because I detect a category confusion in how some Christians discuss moral principles, particularly in their application to the public square. That confusion manifests as a failure to distinguish the source of morality from its reasoned accessibility. So, the argument goes, “God established these moral principles; therefore, that is what obliges them.” That is true, from the vantage point of Christian revelation. We believe that all moral facts originate from the character of God.
Christians are, after all, moral realists. By definition, moral realism is the branch of ethics that holds that moral truths are objective facts tethered to reality as it truly is. Thus, torture does not appear evil or merely invites unpleasant emotions; it is a pre-moral evil. To say that we are moral realists is to assert that what we believe is right or wrong corresponds to true facts about the world we live in.
A failure to understand the nature of this morality—a morality fitted to creation order as such—without accounting for its intrinsic truth-aptness risks falling into theological voluntarism—as though God imposes a morality intelligible by divine decree alone and divorced from the intrinsic reasonableness of this creationally given morality.
But the fact that the authorizing agent of morality is God is a separate issue from whether this moral system is inherently reasonable on its own terms.
What morality is is therefore also a question of underlying logic—not merely of origin.
Christian morality is the morality fit for human beings as human beings. It corresponds to what our nature is. We derive this first from creation order—that God made the world with intelligent design and purpose, and moral order is “baked” into the structure of creation. Second, as man is made in God’s image, we insist that human beings possess rational moral faculties precisely because they bear God’s image. The ability to perceive moral truth is not accidental—it is creaturely. The atheist who shakes his fist at God would still protest having his wallet stolen. Third, Scripture attests to this morality without contradicting the moral order within creation. Scripture clarifies and confirms what distorted moral faculties are apt to misperceive because of sin. Scripture is thus a republication of the moral decrees inscribed within creation.
Practically speaking, then, 2+2=4 is a true statement regardless of whether one can determine where math came from. So the same is true of morality: that murder is wrong corresponds to a moral fact that human beings are apt to perceive as true precisely because they are beings who can perceive such truths, irrespective of whether they can explain from where this moral fact derives. Telling the atheist they should not murder by appealing to Exodus 20:13 is right and good. But this misses the larger horizon about the intrinsic reasonableness of not murdering. Quoting Scripture that the atheist disagrees with does not lessen the degree of obligation that the atheist is required to follow, if only because the atheist in question participates in the creation order that they deny divine authorship over.
Let’s use another example. When someone touches a hot stove, they immediately pull their hand back, wincing in pain. No one needs a theology degree to know that touching one’s hand to a stove produces pain. That’s a fact about reality and human biology. Whether Christian or not, touching a hot stove damages human tissue. Now, a Christian can ultimately explain why the pain-response mechanism triggers as it does—God created embodied creatures with sensory feedback mechanisms for their protection and flourishing. A Darwinist could offer their own explanation, but both the Christian and the Darwinist would land on the same conclusion: Burning oneself is bad. The disagreement is not about the content of the action of putting one’s hand on a hot stove—the disagreement springs from a question of moral origins. The same is true in other debates, even when the topics are more complex. Someone’s morality is fitted properly to human nature, and someone’s is not.
Moral responses work similarly, whether Christian or non-Christian. For example, the revulsion toward mass shootings is not merely born of preference or cultural conditioning. It is a moral perception registering contact with a real moral wrong. The Christian and the atheist experience this alike. What the Christian can do that the atheist cannot is explain why something like a mass shooting is truly, finally, and ontologically wrong rather than just based in evolutionary adaptation.
Here’s why this conversation matters so urgently and practically: Christians who insist that morality is only sensible with God as its reference point risk overlooking whether moral claims are reasonable on their own terms. Either murder is reasonable, or it’s not. Being faithful to one’s spouse is either reasonable or it’s not. Adding a Bible verse to the end of our moral pronouncement may invoke divine authority. What it does not do is make the moral claim truer than it already is or more accessible than it already is. It’s not that God is irrelevant to morality (of course not!); it’s a question of whether God’s morality in the natural law is itself intelligible on its own grounds and corresponds to the order that all human beings inhabit. Please do not interpret me as calling for any less biblical pronouncements. Instead, hear me making a plea that biblical pronouncements testify to enduring moral principles that are reasonable on their own terms. What we can say, though, is that while the atheist may discern a morally true statement, they lack the grounding to express why that true statement is real in an ontological sense.
God is necessary for objective morality to have true, absolute, and final grounding. But necessity is a separate issue from intelligibility. Caring for one’s children, obeying traffic laws, and not stealing are all true, regardless of whether one accepts divine revelation—precisely because the moral law “written on the heart” corresponds to the order of creation and because human beings, whose minds are clouded by sin, are still nonetheless capable of grasping elementary first principles.
To this point, we may turn to C.S. Lewis, who wrote in Miracles,
“I believe that the primary moral principles on which all others depend are rationally perceived…Their intrinsic reasonableness shines by its own light. It is because all morality is based on such self-evident principles that we can say to a man, when we recall him to right conduct, ‘Be reasonable.’”
Here, Lewis articulates the truth that all moral claims, at their deepest level, stem from an underived first principle. That first principle we can say, on the one hand, originates from the creative will of God, but on the other hand, the intelligibility of that indemonstrable truth is expressed in the creature’s reflexive God-endowed intuition that moral principles correspond to an innate moral code befitting their nature as morally-discerning creatures.
When Christians bear witness to Scripture’s moral principles, we are also saying that these moral principles are fitted to human beings as such. If this is true, then morality does not need the adjective “Christian” in front of it (I say that in jest, but you get my point). Why? Because Christian morality is morality. Period.
