This inquiry begins with a question: Does natural law bear moral authority? Is it possible to find in the nature of things created any sort of moral imperative that would bring about human flourishing? The answer seems both simple and complicated.

This post is will not answer all of your questions. My strength is not in Aristotelean-Thomistic natural law theory. This is an area where I am only beginning to read. There are things of value in this field. Francis Schaeffer appealed to natural law as he defined his apologetic, an attempt to find that middle point-of-contract between Christian and other worldviews while simultaneously acknowledging the discontinuity of the foundation of each.

The question bothers me deeply. It seems to allow for moral truth apart from revealed truth, a sort of qualified or Christianized utilitarianism, whereby the world can progress without an appeal to divine authority. I see dangers here. The first is that the concern is not recognized. The second is that this is beginning to sound an awful lot like deism, at least in practice.

Let’s go ahead and work through the issue.

Ed Feser gives a qualified Yes to the question. He takes a providential perspective on morality.

And it is because immanent teleology is real that natural law is possible.  When we study ethics, we are studying what is good for human beings given their nature, not capricious divine commands.  Ultimately the facts studied by science and the facts studied by ethics depend on God, because everything depends, at every instant, on God.

Here he sets up the requirement that God is necessary even if He remains behind the scenes. Yet he goes further, stating that

All the same, since to a large extent the grounds and content of morality can be known from a study of human nature alone, it follows that to a large extent morality would be what it is even if human beings existed and God did not.  For, again, morality is not based in arbitrary divine commands any more than scientific laws are expressions of some arbitrary divine whim.  From the A-T point of view, “divine command theory” (or at least the crude version of divine command theory that takes the grounds and content of morality to rest on sheer divine fiat) is, I would say, comparable to occasionalism, and similarly objectionable.

In response to this I would again appeal to both Feyerabend and VanTil. Our Thomistic sense of natural law says finds its foundation, or should I rather say its limitations, in Christian theology.   Why, for instance, should we not cut off the hands of thieves? The Christian says no based on a limitation in the Bible where the principle is established that the punishment is not to be greater than the crime. (That’s what “an eye for an eye” means. It is not stated as a promise but rather as a limit on vengeance.)

Mr. Feser answers this as well. But not very well. He finds Reason the source for law in a way that is equal to revealed truth, i.e. divine revelation.

The natural law differs, then, from law that is directly given by God via a special revelation, as with the law given to Israel through Moses.  Knowledge of the latter requires knowledge of certain specific historical events and of certain miracles associated with those events.  The natural law is not like that; it is in principle available to all men simply by virtue of being rational and capable of knowing what is good or bad for them given their distinctive nature.  Thus does Aquinas distinguish natural law from divine law.

And (discussing how to answer questions of sexual morality using any of several theological approaches)

That is not to say that these theological approaches to do not have value.  The point is rather that they are not and cannot be complete accounts of sexual morality.  They can supplement what we know from natural reason, but cannot replace it.  For grace builds on nature.

This is where problems arise in my understanding of natural law. We in the Christian “west” accept natural law as it has been informed by Christian theology.

The most bothersome point here is that reason is treated as primary and revelation (theology systematized) exists as support. Theology supplements reason. This is the position of the Rationalist.

My follow-up question goes to that question of context: Could this world have developed as-is without Christian theology but with reason as the primary source for truth? I think not.

What does natural law teach us apart from Christian theology (divine law)? I think very little. For instance, let’s raise the question: Is murder (the taking of life outside of civil law) wrong? Any answer to this question must take into regard the human context. Every culture has a varying set of laws. There may be consensus among the nations with a Christian heritage but outside of that it varies greatly.

Now, one might say that, even though the application varies, the principle remains intact. That is not the case. Reason directed the Canaanites to burn their children, the Hindus to burn widows, the beheading of infidels, the progressive movement with its eugenics practice, and so forth. There is no universal and accepted positive law for human flourishing for the well-being of all. The categorical imperative required a Christian context. It could not have been written anywhere else.

To summarize: We have reason as a source for truth alongside revealed, divine truth. That duality seems damaging. It does not simply require that revelation be filtered through our reasoning faculties but that it is only to be acknowledged through Reason. What does not appear reasonable cannot be divine, or so it seems. Such is the reasoning of both Jehovah’s Witness teaching and the Rationalist.

We have reason taken out of historical context. Reason is treated as though it is some quality to which anyone might grasp as onto some moral certitude. One plus one does equal two but to contains no moral imperative. It is natural and it is a mathematical law. It also conforms to the constraints of Reason. But questions of life and death, or ethics and morals, these are, to be found either in Reason or in the Divine. Establishing a dualism between the two does not resolve questions of what is actually right or wrong. It adds an additional source of authority. This appears consistent with Roman theology and its dependence on authority and tradition, but not with Reformed thought.

These questions force me to ask whether natural law is even a valid category.

In the end I find that there is a sort of morality without God.  People do make positive choices to the end of their own betterment and the betterment of others.  But there is no consistency in human behavior.  The world is as violent and rebellious, as bloody and war-ravaged as it has ever been.  There are fewer wars these days but the ones we have are larger.  A good deal of bloodshed takes place in the dark, ignored often for political purposes.

The morality of divine revelation is not to be found in nature.  Nature is read in tooth and claw. Redemption in Christ was bloody for the last time, having the intention of grace informing nature rather than the other way around.