I am grateful for the invitation to give this lecture, both for the opportunity to serve the presbytery and to learn from you as I continue my own work on the subject of natural law. I know that this can be a controversial topic. Before I begin I should offer a brief definition of natural law: it is a law given by God, defining human beings’ basic moral obligations and the consequences of obedience and disobedience, revealed objectively in the natural world and known subjectively by rational human beings who are constantly confronted by the natural world, though sinfully prone to twist its meaning.
In the first section I offer historical reflections. I conclude that natural law simply is a part of the historic Reformed system of doctrine and intimately woven into the Westminster Standards. Thus, I believe the question before us as Reformed Christians is not whether we have a theology of natural law, but what kind. In the second section, therefore, I present an outline of how a good Reformed biblical theology of natural law might be constructively developed.
A number of concerns make many contemporary Reformed Christians anxious or even agitated when they hear a fellow Reformed believer saying a positive word about natural law. The concerns often run along the following lines: the idea of natural law entails too high a view of the powers of human reason (and hence too weak a view of human sin); it detracts from the supreme authority of Scripture (and hence compromises the doctrine of sola scriptura); and it promotes a vision of ethics based on human autonomy (and hence without the immediate need to take God into account).
These concerns about natural law are valid. They are valid if we understand natural law in the way proponents of the Enlightenment increasingly understood it. After a long period of religious wars and social unrest following the Reformation, many European intellectuals wished to find a way to unite people across traditional confessional divides, through the common and universal powers of human reason, unencumbered by detailed theological convictions. They adapted the idea of natural law to serve this end. Natural law became a tool for constructing a universal human ethic, unhooked from the deep theological doctrines that Christians had traditionally used to talk about natural law. This Enlightenment perspective did indeed have too great a confidence in reason, have too low a view of Scripture, and promote an autonomous human ethic.
The concerns that many contemporary Reformed Christians have about natural law, however, are not valid with respect to historic Reformed views of this subject. In many respects they are not even valid with respect to medieval views of it. It is fascinating, furthermore, that many contemporary natural law theorists—from various points on the Christian theological spectrum—are saying that we need to get away from these Enlightenment ideas about natural law and recover older approaches to the subject that reconnect it to biblical teaching and rich theological doctrines. In light of this, I now reflect briefly on natural law from the Middle Ages through the Reformation era, concluding with the place of natural law in the Westminster Standards.
In the Middle Ages, theologians, philosophers, and jurists all wrote about and utilized natural law. Though they had some internal disputes about certain aspects of natural law, there was widespread consensus on many important points. They agreed that the natural law exists. They believed that God himself had created the natural order and the human conscience that perceives it and responds to it, and thus they believed that the natural law placed people under obligation to God. These medieval thinkers also taught that sin has damaged the human person’s ability to understand and to follow the natural law. On the practical side, they commonly spoke about natural law as foundational for civil law (though in a flexible way, requiring prudential application to particular circumstances). Finally, they believed that natural law and biblical moral teaching should be mutually illuminating, neither of them to be explored completely independently of the other. I do not mean to suggest that medieval natural law was perfect. It was not. But medieval thinkers did think about natural law in biblical and theological terms.
As far as I can tell, the Reformers looked at natural law as a part of catholic Christianity that stood in no great need of reform. The Reformers obviously thought that many aspects of Christian doctrine needed serious reform—issues such as justification, the sacraments, and the relationship of biblical and ecclesiastical authority among the most familiar to us. But they did not view many other aspects of their doctrinal inheritance in this way—the doctrine of the Trinity and the two natures of Christ, for example. Natural law, it seems, fell into the latter category.
This is not to deny, however, that there were some shifts in perspective on natural law among the Reformers and their heirs, even if they did not take up natural law as a point of focus for their reforms. Compared to their medieval forbears they had an enhanced sense of the dreadful effects of sin and its noetic effects, and hence also an enhanced sense of the necessity of Scripture to clarify and correct their interpretation of what the natural law reveals. The Reformers also developed an understanding of the conscience in some new directions, which in turn shaped certain aspects of their doctrine of natural law. In connection with the doctrine of the two kingdoms, furthermore, we find Reformers making clearer distinctions between the role of natural law with respect to “earthly things” and its role with respect to “heavenly things” (to borrow John Calvin’s language), such that natural law could play a rather positive function for the former while for the latter serving only the negative function of convicting people of their sins and driving them to a Savior. In other words, God gave natural law a positive role in helping to promote a measure of social order and cultural achievement in this world, but it could not constructively advance a person one step toward a right relationship with God or eternal life.
I believe there is more work to do in developing a Reformed theology of natural law that is biblically penetrating and consistent with our broader doctrinal commitments. But, before I turn to that subject, it is worth reflecting on how natural law became thoroughly integrated into the Reformed system of doctrine and confessional standards.
As far as I can tell, older Reformed theologians never made much effort to build a distinctively Reformed theology of natural law, but they all affirmed the existence of natural law, and they incorporated it into their theology. The Westminster Standards illustrate this. I have counted at least thirteen direct references to natural law in the standards (which uses various terms, such as “light of nature,” the “law of God written in their hearts,” and “law of nature”), and there are also indirect references. But perhaps more significant than the sheer number of references is the range of Reformed doctrines that the standards connect to natural law. This means that one cannot extract natural law from the system of doctrine taught in the standards without fundamentally damaging the system itself. Natural law is integral to the historic Reformed system of doctrine.
What doctrines do the standards associate with natural law in one way or another? One is the existence of God: “The very light of nature in man . . . declare[s] plainly that there is a God” (Westminster Larger Catechism 2). (This refers to natural revelation more broadly, and not simply to natural law.) Another is the nature of human beings as created under the covenant of works. Westminster Confession of Faith 4.2 and WLC 17 describe the first humans as “having the law of God written in their hearts, and power to fulfil it.” The standards also appeal to natural law to describe the most basic moral commitment that continues to bind all people after the fall into sin: “The light of nature showeth that there is a God, who hath lordship and sovereignty over all, is good, and doth good unto all, and is therefore to be feared, loved, praised, called upon, trusted in, and served, with all the heart, and with all the soul, and with all the might” (WCF 21.1). The Sabbath is another important moral issue the standards associate with natural law: “It is the law of nature, that, in general, a due proportion of time be set apart for the worship of God” (WCF 21.7). Of course, the standards also hold that all people rebel against this natural moral revelation. This means that there is no salvation for anyone apart from the word of Scripture, be they “never so diligent to frame their lives according to the light of nature” (WCF 10.4; WLC 60). WLC 151 also speaks of the “light of nature” when explaining the heinousness of sin. And natural law ensures the accountability of all people before God at the final judgment: “The light of nature, and the works of creation and providence do so far manifest the goodness, wisdom, and power of God, as to leave men unexcusable” (WCF 1.1).
Natural law, furthermore, plays positive roles for believers and the church, according to the Westminster Standards. It helps us to understand the bounds of our Christian liberty, for example, for Christian liberty does not permit us to publish opinions or maintain practices that are “contrary to the light of nature” (WCF 20.4). Natural law is also necessary for the proper ordering of worship and ecclesiastical government. In the very section explaining the sufficiency of Scripture, the WCF states: “There are some circumstances concerning the worship of God, and government of the church, common to human actions and societies, which are to be ordered by the light of nature” (1.6). WCF 1.6 provides a helpful reminder: in classic Reformed theology, the doctrine of sola scriptura means that we do not need other forms of special revelation, not that we do not need natural revelation. Scripture itself presumes the existence, and continuing importance, of natural revelation.
In light of all this, I believe that we who are confessional Presbyterians do not have an option about whether to affirm a robust doctrine of natural law as part of our system of doctrine. Our challenge is to develop a theology of natural law from Scripture that best illuminates and further refines this confessional material.
This second section describes how I think a biblical theology of natural law might be constructively developed, in ways consistent with and supportive of the Reformed system of doctrine. First I reflect on a covenantal theology of nature and then turn to the importance of natural law with respect to unbelievers and believers.
First, I suggest that a Reformed theology of natural law should be grounded in a theology of nature, which in turn should be grounded in our covenant theology. When thinking about a theology of nature, it makes sense first to consider Genesis 1 and the original covenant of works. Genesis 1 makes immediately clear that God’s creating activity instills the entire natural world with order and purpose. His creation is objectively meaningful. Another thing Genesis 1 explicitly teaches is that God made human beings in his image, and this image entailed knowledge, righteousness, and holiness (Eph. 4:24; Col. 3:10). Human beings were thus subjectively capable of comprehending and acting upon the truth communicated in nature. To say that the natural order is objectively meaningful and that human beings are subjectively capable of apprehending its meaning may seem like obvious assertions to many Christians, but they are crucial foundation to a theology of natural law, and they emerge already from Genesis 1. We also observe in Genesis 1 that God made man in his image for the purpose of exercising dominion in the world. God had exercised supreme dominion in creating the world, and man, according to his likeness, was to rule the world under him. If man was to rule the world in God’s likeness, he had to rule it not aimlessly but toward a goal, for God himself worked, then passed through his own judgment (Gen 1:31), and finally rested. As taught in our doctrine of the covenant of works, God made man to work, then to pass through his judgment, and finally to join him in his eschatological rest. Genesis 1, I believe, does not allow us to separate our doctrine of the image of God from the covenant of works, as if the latter were simply added on at some point after man’s creation. God made human beings by nature to work in this world and then to attain eschatological life. Thus the original order of nature communicated not only man’s basic moral obligations toward God but also the fact that God would judge him for his response and reward or punish him accordingly.
In light of the fall, however, we cannot simply view natural law now through the lens of the original creation. Accordingly, I suggest that it is helpful to view natural law in the present world through the lens of the covenant with Noah in Genesis 8:20–9:17, for this is the means by which God now preserves and governs both the cosmic and social realms. This covenant makes clear that God still orders the cosmos and makes it objectively meaningful, though its purposes have been obscured, and that he still deals with all human beings as his image-bearers, though they are fallen. God gives human beings responsibilities adapted for a fallen world, but these responsibilities resemble those under the original creation order. We are to be fruitful and multiply, to rule the animals responsibly, and to pursue justice (Gen 9:1–7). God did not impose these obligations arbitrarily; they correspond to the nature with which he created us. The very commission to do justice is grounded in human nature: “Whoever sheds the blood of man, by man shall his blood be shed, for God made man in his own image” (9:6).
God’s original work of creation and his providential governance of the fallen world under the Noahic covenant, therefore, provide crucial foundation for developing a theology of natural law. But how does the rest of Scripture speak about natural law and its purposes? In what follows, I identify aspects of biblical teaching that show the importance of natural law with respect to unbelievers and then with respect to believers.
There are at least three important functions of natural law with respect to unbelievers. First, natural law is a tool of common grace for the preservation of human society. This corresponds to what is often termed the second use of the law. The story of Abraham and Abimelech in Genesis 20 provides a good illustration. Sojourning in Gerar, Abraham deceived king Abimelech by calling Sarah his sister, and Abimelech promptly took her into his home. Informed of the real situation by God in a dream, Abimelech confronted Abraham the next morning. Though they came from different places, cultures, and religions, Abimelech accused him: “You have done to me things that ought not to be done” (20:9). This pagan recognized a universal standard of morality, cutting across cultural and ethnic divides, that one person should be able to expect any other person to acknowledge. Abraham’s response—“I did it because I thought, There is no fear of God at all in this place, and they will kill me because of my wife” (20:11)—displays that he had misjudged Gerar. There was indeed a certain (non-redemptive) fear of God in this place that restrained the outbreak of sin. The natural law is an instrument of common grace.
Second, natural law is a means for bringing all people under God’s universal judgment. Romans 1 provides a clear example. In 1:18–21 Paul teaches that all people are without excuse before God and stand under his wrath because of what can be known about him “in the things that have been made.” Through creation itself they know God, though they constantly distort this knowledge. Among their sins, they give up “natural relations for those that are contrary to nature” (1:26). Paul also states that through this natural revelation they “know God’s decree that those who practice such things deserve to die” (1:32). The picture is not absolutely negative, for Paul later adds that Gentiles also “by nature do what the law requires” (2:14). But this internal knowledge of God’s law involves judgments of the conscience that serve as a foretaste of the final judgment: “They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them, on that day when, according to my gospel, God judges the secrets of men by Christ Jesus” (2:15–16).
Third, natural law is important for unbelievers because it lays necessary foundation for proclaiming the gospel. This corresponds to the so-called first use of the law. The previously quoted verses from Romans 1–2, of course, are part of Paul’s own foundational teaching in preparation for his explanation of justification and other saving benefits, beginning in Romans 3:21. In short, without the law there is no gospel. Without conviction of sin there can be no faith and repentance. Calling attention to the testimony of natural law, therefore, promotes the effective preaching of salvation in Christ.
Finally, I turn to the importance of natural law for believers. Here again I mention three basic considerations. First, natural law rebukes us when we stray. The function of natural law described in Romans 2:14–15 does not entirely cease in people who come to faith, for it continues to prick our consciences concerning sin. The Old Testament prophets frequently appealed to Israel’s knowledge of the natural world and the way it works in order to help the people understand the utter ridiculousness of their rebellion against God (e.g., Isa. 1:2–3; Jer. 8:7). Understandably, there are fewer examples of this in the New Testament, but consider Paul’s statement: “It is actually reported that there is sexual immorality among you, and of a kind that is not tolerated even among pagans, for a man has his father’s wife” (1 Cor. 5:1). His comment only makes sense if pagans are aware of a universal moral truth. Paul awakens believers’ consciences by shaming them through the natural law.
Second, natural law shows believers how we are to live well in a dangerous world. Scripture makes clear that the moral life is not just about memorizing rules, but also about observing the world, learning how things work, and drawing appropriate moral conclusions. The wisdom commended in Proverbs is inconceivable without natural law. The structure of the universe is suffused with God’s wisdom, by which he made it (Prov. 8:22–31), and by perceiving and following this wisdom human beings find success and blessing in the world (8:15–21, 32–36). Observation of the world should lead believers to conclusions about how it regularly operates, and this in turn should compel certain moral conclusions. For example, observing the ant (6:6–8) and the sluggard’s vineyard (24:30–34) warn against laziness.
Third, natural law explains and reinforces for us, as New Testament saints, why we continue to honor and participate in the natural institutions of this world (such as family and state), though we are already citizens of a heavenly kingdom that does not have such institutions. Christ did not establish any institution except the church, and he did not create any brand new obligations toward the family or state. With regard to such institutions the New Testament echoes and reinforces obligations that are already there under the natural law (though we are now to pursue them “in Christ”). Commands about marital fidelity, raising children, pursuing justice, and honoring magistrates are not arbitrary, but are appropriate for the kind of people God made us by nature. Romans 13:1–7, for instance, reflects the natural order preserved under the Noahic covenant, in which God ordained the use of the sword by his image-bearers to enforce justice against evildoers (Gen 9:6). And both Jesus and Paul appealed to the creation order to explain their exhortations about marriage and sexual morality (Matt. 19:3–9; Mark 10:2–12; 1 Cor. 11:2–16). It is true—and I believe very important to remember—that Christians are also called to witness by their conduct that they ultimately belong to the new creation, where the natural order in the form we now know it will no longer exist. Our non-retributive, reconciliation-seeking church discipline, which looks so different from the way the state is to deal with wrongdoing, is a good example. But as long as we live in this present age, the reality of the natural law explains our continuing obligation to honor natural institutions.
Having offered these historical reflections and biblical suggestions, I conclude with three basic reasons why we should recover a Reformed theology of natural law. We should do so, first, in order to be faithful to our Presbyterian confessional tradition (as well as to show that we are true heirs of catholic Christianity). We should recover a Reformed theology of natural law, secondly, in order to be better able to teach the whole counsel of God from the Scriptures. Finally, this endeavor will help us to understand better the ways by which God upholds human society through his common grace and thus to understand better how to make our way as sojourners in this world and to proclaim the gospel faithfully within it.
 This essay is a shortened and edited version of a lecture given at the pre-presbytery theology conference of the Presbytery of the Midwest (OPC), in Grayslake, IL, March 2011.
David VanDrunen, a minister in the Orthodox Presbyterian Church, is the Robert B. Strimple Professor of Systematic Theology and Christian Ethics at Westminster Seminary California. Ordained Servant Online, April 2012.