Karl Barth was one of the most formidable critics of natural law theology in the 20th century. He was wrong to reject it, but the danger he identified—the corruption of natural law reasoning into ideological justification for racial hierarchy—was real. It’s real again now, as recent social media eruptions make plain.
In the 1930s, German Christians used the language of natural order to baptize National Socialism. God was speaking through blood, soil, race, and national destiny, or so they claimed. In this view, what is naturally occurring takes on the force of divine mandate. Barth saw this flattened-out appeal to natural law, which confuses natural for naturalism, for what it was: ideology draped in theological justification. Ironically, arguments of this nature take on an almost Darwinian hue—arguing from natural fact to moral duty (a form of the naturalistic fallacy).
Barth’s prescription was too radical in dispensing with the idea of natural law altogether. But his diagnosis of what could go wrong was justified. A similar mistake was present in Aristotle’s natural law theory, wherein he invoked the category of natural law to classify persons as natural slaves because of a supposedly lower nature. What Aristotle did is what Barth feared would follow from appeals to natural law absent God’s revelation in Scripture—mapping a desirable social outcome onto “nature” in reverse to justify a preferred social paradigm.
Which brings me to something happening in certain circles today.
Kinism—the position that racial and ethnic separation is an unchanging creational norm, that there is a moral commission to maintain ethnic boundaries, that God inscribed ethnic hierarchy into the natural order, that Genesis 10 prescribes ethnic homogeneity as a moral imperative—is precisely the corruption Barth feared would come by appealing to naked appeals to “nature.” It takes the vocabulary of creation order—what is ostensibly “natural”—and arrives at conclusions the tradition never drew and cannot support. Nazi race ideology was the fulfillment of his fears.
This is not what natural law means. “Natural” does not mean whatever occurs has a moral mandate attached to it.
Classical natural law theory reasons from human nature and the goods that comprise it. Not German nature or German goods. Not Anglo-Saxon nature or Anglo-Saxon goods. Human nature and human goods. The imago Dei is not parceled out along ethnic lines. The moral law written on the conscience is written on every conscience. The natural law tradition is universal by definition, because human nature is universal. Ethnic differentiation in Scripture and in nature carries no inherent moral freight or moral mandate to preserve for its own sake. Ethnic differentiation just is, which we can celebrate as a reflection of the diversity stamped upon creation. Human beings are chiefly classified by their participation in the human community, not by ethnic or racial differences.
It’s just exegetically wrong to argue that God encoded racial separation into the creational order. This is a corrupted view of nature and an ignorant posture toward the unfolding of history and the rich and irreducible diversity of peoples. At best, we can call our ethnic identity and geographic identity a “providential good”—a good to be honored and stewarded (never with one ethnicity deemed superior or subordinate to another) but not statically held as an enduring obligation or fixed boundary. Natural law has very little to say about the exact composition of a nation’s population, and good-faith disagreements can exist on the degree of ethnic and cultural homogeneity necessary for social stability.
Even I will grant that the immigration regime of the last 60 years has been deeply disruptive. That does not, though, invite a justification to create rigid, extra-biblical categories for racial purity or racial segregation. Biblical prudence about immigration does not dictate a rigid precision about what level of ethnic diversity a nation requires. Grounding this in a moral mandate goes beyond what Scripture spells out.
The existence of this corruption does not vindicate Barth’s wholesale rejection of natural law, any more than the existence of bad exegesis justifies abandoning Scripture. The answer to corrupted natural law reasoning is better natural law reasoning, better theology, and better exegesis—more rigorous, more historically honest, more philosophically disciplined.
But the corruption we see at present, with a growing chorus of online edgelords playing cute with Nazi iconography and racial realists calling for each group to preserve its own lineage, is real and should be named. Not only is this view truncated—it is sophistry dressed up to promote sinful favoritism and rebellion against God’s good design.
If you are in Christian circles and hearing arguments that dress ethnic nationalism in the language of creation order—arguments about Babel as a racial separation mandate, about natural affection as a theological warrant for ethnic hierarchy—you are engaging not the Christian natural law tradition but a corruption of it (and bad exegesis, since the Babel narrative is about divine restraint on human overreach, not a timeless ethnic separation mandate). You are making the same shortsighted and erroneous arguments that ultimately undermine natural law and invite unvarnished bigotries—just like what transpired in 1930s Germany.
We need not dispense with the natural law tradition just because it is abused. As goes the phrase abusus non tollit usum—the misuse of something does not negate its proper use.
This article originally appeared at WORLD Opinions on June 19, 2026.
