Can we make effective arguments from natural law in the public square in our culture today? Many say that Christians should not use the Bible in making political and cultural arguments. Instead, we ought to argue from something more universally recognized, such as nature or reason. While I firmly believe that we can and should use arguments drawn from reflection on nature (or natural revelation, as we Christians call it), I do not think we should sideline the Scriptures. And I am not convinced that arguments based on nature have an intrinsic advantage over arguments based on Scripture even in the public square. In reality, these kinds of arguments share quite a bit in common and should actually be used to complement one another.
First an observation: If natural law arguments could be effective today, why don't we see their effectiveness on display when it comes to issues like homosexuality, transgenderism, and so on? Natural law arguments have been made in all these areas but do not seem to have made any more of a dent in progressivism's cultural dominance than arguments from the Bible have. Why is natural law failing to persuade, despite the fact there are many articulate natural lawyers speaking to the most divisive topics in our culture?
Here is the basic issue: People who don’t believe in the Triune God of the Bible don’t believe in nature either, at least not "nature" in the sense required to support natural law. There is only a natural law if there is a Creator who designed the world a certain way and reveals his character (and thus makes moral demands) through what he has made. Of course we know such a God exists -- the Bible tells me so (Rom. 1:18ff)! But note what this means: an argument from natural law is just as theological as an argument from Scripture. In fact an argument drawn from natural law (if it is a good and true argument) is based on God -- indeed the same God -- as an argument drawn from Genesis or Romans or the Sermon on the Mount. Nature and Scripture both come from the same God and reveal the same God. If an unbeliever rejects and suppresses one form of revelation, he will do so with the other form of revelation as well. Nature does not give us a more pagan-friendly deity. Nature does not reveal a generic "higher power." Nature reveals the God who wrote the Bible and entered history in the man Jesus. It's all of one piece, one seamless fabric.
All this to say: There is no neutrality. If you hate the God of the Bible, you will also hate the God of nature. If you reject the Redeemer, you cannot be on good terms with your Creator since they are one and the same.
This means that arguments drawn from nature will not fare better in the public square than arguments drawn from Scripture, and might even fare worse since they can be more difficult to develop. Exegeting Scripture can be a challenge at times, but exegeting nature is just as difficult, and sometimes even more difficult.
Scripture actually gives us the divine ethic in an easier to understand form; it gives is a "shortcut" in grasping what God requires of us. Further, even before the fall, God intended man to interpret nature through the lens of Scripture (cf. Gen. 2:16-17; Calvin, Van Til, and Frame, make this point).
The best use of natural law is not to develop an ethical system independently of Scripture, but to help us more fully understand why God has given us the commands that he has in Scripture. Thus, natural law arguments can serve an apologetic purpose, showing that biblical law meshes perfectly with human nature. Biblical law "fits" us like a hand in a glove. Natural law unpacks the rationale for the biblical commandments. Sure, natural law can also arrive at ethical imperatives based on an understanding of how and why God made the world as he did. But biblical law is actually easier to comprehend in most cases. So why do things the hard way, when we have Bibles readily available?
Natural law arguments are developed by reflecting on God's design in the creation; thus, I would rather speak of “creational design” instead of “natural law." But whatever we call it, there is no indication that God ever intended natural revelation to function apart from special revelation, anymore than God intended special revelation to operate apart from natural revelation. Adam had both in the beginning; we have both as well, and we are responsible to use both.
But there is another reason why natural law arguments, drawn from reflections on creational design, do not carry the weight that they should today.
Natural law arguments largely lost their force in Western culture after Darwin’s theory of evolution replaced the creation account of Genesis in people's worldviews and imaginations. Evolution means there are no fixed natures in the cosmos; everything is in flux and there is no Designer behind it all. Given evolutionary theory, anything can become anything. The universe is nothing more than matter in motion, governed by time and chance.
So if arguments from Scripture are not effective because most people no longer see the Bible as the inspired and inerrant Word of God, and if arguments from nature no longer work because people no longer believe in a Divine Designer, then what should we do? Simple: We should continue making arguments from Scripture and nature. And we have to trust that God will use reasonable appeals to his Word and to the design of his world when and how he pleases. God has not left himself without a witness. There is plenty of evidence for the Christian worldview; indeed, there is nothing but evidence for the truth of Christian faith. If unbelievers choose to suppress that truth, they are only intensifying their own judgment. Our job is to bear witness to God's truth; it is God's job to change hearts (or not) as he wills.
But I want to come back to an earlier point and develop it a bit more. Again, note that natural law/creational design type arguments have no advantage over biblical arguments in America in 2022. In fact, if I had to choose, I would appeal to God's special revelation in Scripture because it is not only more direct but also because it has a power that natural revelation does not. The Bible is God's two-edged sword, living and active, able to pierce and transform human hearts. Arguments from natural revelation can condemn, but arguments from Scripture can also redeem. At our best, we will use arguments from both forms of revelation, as wisdom and winsomeness dictate. But it would be a real shame for us to leave the sword of the Spirit in its sheath when God has equipped us for war with precisely this weapon above all others. The goal of our cultural witness is not to get people to respect or bow before nature; that would just perpetuate their idolatry. We want them to worship nature's God. Or to be more specific, our goal is to get people to kiss the Son (in the words of Psalm 2). The Lord Jesus rules over all; he created nature and governs nature, and he has come into our world to be our Savior and King. Christian witness in the public square always falls short of the goal if fixates on nature and does not get to Jesus. We should make appeals to nature, to be sure, since it reveals the wisdom and power of God. But we also point to the one who is the ultimate embodiment of God's wisdom and power, Jesus Christ.
Finally consider how an historical example might help us. We actually have an example of arguments from Scripture and nature complementing one another, and very effectively, from the not too distant past in our nation's history. While the civil rights movement had all kinds of problems, it also corrected some significant and very real injustices. The Reverend Martin Luther King, Jr.'s rhetoric appealed to natural law but also to the Bible. This can be seen especially in what is perhaps his finest work, "Letter from a Birmingham Jail." Frankly, I would suggest his biblical arguments were actually more decisive in persuading Americans of the evil of segregation than his arguments from natural law. Creation eloquently testifies to God's intentions for the human race, but Amos and Paul even more so.
Could someone make arguments similar to those of King today, with the same degree of effectiveness? Obviously, King operated in a context in which the Christian faith was still dominant in the consciousness of America. That is no longer the case now, as we have entered into what Aaron Renn has called "the negative world." But not all is lost. Our culture has not completely moved beyond its Christian heritage, even as we have sunk into widespread apostasy. What we see in progressivism today is that certain Christian/biblical concepts, like rights, equality, empathy, etc., have been cut out of the moral framework from which they came and have been secularized. Tom Holland and Glen Scrivener have addressed this in recent works and while I disagree with certain aspects of their program, they demonstrate an important point. While political progressives do not have Christian hearts or even Christian consciences, they have not escaped the Christian legacy of the West; their secularism cannot support their self-defined virtues, and yet they cling to them tenaciously anyway, unaware that in doing so they are still acting as semi-Christians. Christian moral concepts, even twisted and distorted, still appeal to people in our culture because there is at least a vague memory of Christian faith. Flannery O'Connor called this residue of biblical concepts in a culture that has departed from living faith as being “Christ haunted." And indeed that's what our culture has become: we are not Christ-centered or Christ-honoring, but we are Christ-haunted. But the Christ who haunts us is no ghost. He is the risen Savior, who came forth from the grave bodily on the third day after his death and who now lives and reigns as King of kings and Lord of lords. It may seem for the moment that his double witness in creation and Scripture has lost its power, but that is not the case. Our culture's blindness to the glory of God in creation and especially in Jesus is a sign of judgment, not a sign that the gospel is weakened. When the time is right, when it pleases him, he can open the eyes of the masses to who he is -- the God of nature, the God of Scripture, and the God embodied in Jesus.