We make distinctions among the ceremonial law, the dietary law, the civil law, and the moral law. To the Jew, every law commanded by God in the Old Testament was moral in the sense that it had moral significance to it.
It is a useful distinction to distinguish the moral law from the ceremonial law, because we know that the ceremonial law has been fulfilled in the perfect work of Christ. And we know that the dietary laws have been set apart. They had a historical significance that differs from the moral law of the Old Testament.
We make a distinction in theology between the natural law of the Old Testament and the purposive law of the Old Testament. Now, that’s easy to get confused because we make a distinction also between natural law and revealed law. But that’s not the distinction in view here.
The distinction in view here is there are laws that God gives in the Old Testament (and in the New) that are an expression of His own character that is immutable. So that if He set them aside, He would be doing violence to His own character.
For example, if God would say, “Now in the new covenant it’s okay to worship idols,” God would be denying His own deity and supremacy at that point. But when we talk about purposive laws, we say there are laws of God gave for a specific historical purpose, preparing the world for the fulfillment of those purposive laws in the person and work of Christ.
Now, this is a question that I don’t think would be a mistake for us to talk about the rest of the time here. Because we are living in a time of, since the Reformation, unprecedented antinomianism: the idea that the law of God, particularly the moral law of God in the Old Testament, has no relevance whatsoever for the New Testament Christian.
I remember making a statement years ago that to say that the moral law of the Old Testament has no relevance to the New Testament Christian is antinomianism. I got a letter from a professor at a seminary. He had his Ph.D. in biblical studies, and he said to me, “Why are you calling us antinomians? We’re not antinomians, because we believe in the commandments of Christ. We don’t believe that the Old Testament law is relevant to us, but the New Testament law is.” I said, “What you are now articulating to me is the classic example and definition of antinomianism, because what antinomianism refers to is the Old Testament law and its relevance to us today.”
The Christian ought to be able to say with the psalmist “Oh, how I love your law” (Ps. 119:97).
We make a distinction between the Word of God and the law of God, but God’s Word is His law and His law is His Word. And that moral law is something that the church needs to hold with great precision and care. It’s what Calvin called the tertius usus or the third use of the law: God’s revelation of what is pleasing to Him from His people.
I said at the beginning that I would say yes to all of it, because all the law has its other purpose, the purpose of being the mirror that reflects our sinfulness, that reveals to us the holiness of God. It is the schoolmaster that drives us to Christ. We recite the Ten Commandments or a part of the Ten Commandments every Sunday at St. Andrews. We preach the law so that people can be pushed to the gospel.
And not only that, the moral law has the significance of being a restraint to evildoers. People don’t always obey the speed limit, and maybe if the speed limit is fifty-five they’re driving sixty-five. But without that sign, they would drive eighty-five. So the law has a restraining impact of common grace even in that.