What Is "Natural Law"?

"Natural law is the moral revelation that God gives in creation itself. Romans 1:18-32 speaks of things that may be known of God from creation, including a great deal of moral knowledge. Romans 2:14-15 speaks of the law of God being written on people's hearts, such that even those without access to the law revealed in Scripture are held accountable to God through their consciences. Many prominent Christian theologians have identified natural law as the standard for civil law and government, including not only medieval theologians such as Thomas Aquinas but also reformers such as John Calvin. Thus, acknowledging the importance of natural law is neither unbiblical nor foreign to historic Christian theology.

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When we as Christians come into contact with unbelievers, we eagerly proclaim Scripture's message of salvation to them, with hopes that they will submit to that message and believe in Christ. But even if they do not, we must still deal with them respectfully as fellow citizens with whom we share a common life in the public square. Is it possible to have genuine moral interaction with them on matters of political or social concern, even if they will not accept the authority of Scripture's teaching? Since we are called to live at peace with all people as far as possible (Rom. 12:18), this is undoubtedly an important question.

Here is one area in which natural law becomes a helpful resource. When appealing to natural law, believers need not feel that they are compromising their Christian convictions, for natural law is authoritative and true; it is part of God's own revelation, after all. Neither need Christians fear that they are appealing to a standard that is unknown or foreign to unbelievers; God has inscribed the natural law on the heart of every person (Rom. 2:14-15), and all people know the basic requirements of God's law, even if they suppress that knowledge (Rom. 1:19, 21, 32). Most every unbeliever, in fact, accepts the truth of at least some aspects of the natural law. True, they do not accept it for what it really is, the revelation of the living and triune God. But most people, when pressed, would admit that acts such as murder, stealing, and lying are immoral, and they themselves generally avoid such actions. Most people would also claim that law and government exist to protect people against those who would kill, rob, or defraud them.

The fact that most unbelievers, though refusing to worship the true God, still to some significant extent acknowledge and live by the truth of his law as it is known by nature is something for which Christians can be very grateful. Because of this, societies generally retain some degree of order and justice. And it provides Christians with the opportunity to engage unbelievers in genuine moral dialogue on issues of public policy. But how exactly does one make arguments from natural law and thus put it to use in the public square?"

— David VanDrunen, Natural Law and Christians in the Public Square, Modern Reformation, March/April 2006.