Context and salvation history help us see not all uses are equal.
The word “law” is an important one in the Bible, in the Old Testament, especially, but also in the New. If we read the word and always think it has a single meaning, we will be led astray from what the Holy Spirit is trying to say. Only by reading and comparing can we arrive at the various ways Scripture uses the word. What follows is a survey of these uses.
Law = Scripture.
One of the most general ways the word law is used is to designate God’s revelation in Scripture. Jesus spoke to the Twelve in his post-resurrection days and said, “These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled.” Luke 24:44.
The Law of Moses refers to the Pentateuch, the first 5 books of the Hebrew Bible. Consider also what Paul says in Gal 4:21 “Tell me, you who desire to be under the law, do you not listen to the law?” When he speaks of law, it’s clear Paul is not talking about commandments, for he goes on to discuss events in Genesis 17, long before the giving of the law. What we read later in the chapter solidifies this meaning of law as Scripture. “But what does the Scripture say? ‘Cast out the slave woman and her son, for the son of the slave woman shall not inherit with the son of the free woman.’” Gal 4:30. This is the continuation of the promise of Isaac as heir, again, long before the giving of the law at Sinai.
Finally, Paul writes, “In the Law it is written, ‘By people of strange tongues and by the lips of foreigners will I speak to this people, and even then they will not listen to me, says the Lord.’” 1 Cor 14:21. Paul says it is written in the law, but he quotes from Isaiah, one of the prophets. Clearly, then, he uses law in this broadest sense to mean Scripture.
Law = Commandments given at Sinai
We find a more constrained meaning of the word when it refers to the commandments given by God to the nation of Israel at Sinai. The Ten Words, or Ten Commandments, are the treaty stipulations between God and the seed of Jacob. Paul notes in Romans 2:12-13: “For all who have sinned without the law will also perish without the law, and all who have sinned under the law will be judged by the law. For it is not the hearers of the law who are righteous before God, but the doers of the law who will be justified.” Here is doing of the law, and in the case of Gentiles, sinning apart from the law. Later in the same chapter, he asks, “So, if a man who is uncircumcised keeps the precepts of the law, will not his uncircumcision be regarded as circumcision?” Rom 2:26. It is clear that Paul has precepts, commandments, statutes in mind when he uses the word law here. Finally, in chapter 7 Paul speaks of his own experience and says “I would not have known sin. For I would not have known what it is to covet if the law had not said, ‘You shall not covet.’” Rom 7:7. Paul does not say the Tenth Commandment, though this is the one he cites, but simply, “the law.” This demonstrates another important principle about the word, and its use. The law is a unit that cannot be divided in to moral, civil, ceremonial portions. Israel was on the hook to keep all of it, no exceptions. “The whole commandment that I command you today you shall be careful to do, that you may live and multiply, and go in and possess the land that the Lord swore to give to your fathers.” Deut. 8:1.
Law = synonym for principle
Some doubt this use of the word, but there is a case to be made for it. Paul says, “I find it to be a law that when I want to do right, evil lies close at hand.”16 Substitute the word “principle” here, and it becomes clear what the apostle is saying. Think of the “law of gravity” and this is an analogy. Leon Morris affirms that, aside from the clear references to the Mosaic law, Paul sometimes uses the word in this more general sense: “In addition to these more or less straightforward uses of the term Paul has a number of other expressions. He can speak of ‘the law of faith’ and of ‘the law of works’ ([Romans] 3:27; NIV translates with ‘principle,’ and Hodge thinks the word here means ‘a rule of action’).” Not all agree on the extent of this. Some, indeed, see references to the Mosaic law, where others assign this more general sense to the word.
Law of Christ = lowly service and self-giving sacrifice
Some want to make what Paul says in Galatians 6 as a kind of rehabilitated law of Moses, that being now sealed and indwelt by the Holy Spirit, we are at last empowered to keep the law. But such a view does not make sense. Paul writes, “Bear one another’s burdens, and so fulfill the law of Christ.” Gal 6:2. Paul here links helping others, supporting others, bearing the burdens of others—not obeying the commands given at Sinai—with the law of Christ. He can term it the law of Christ because Jesus’ death on the cross was the supreme burden-bearing. “He himself bore our sins in his body on the tree.” 1 Pet. 2:24 Indeed, even Calvin himself writes,
“There is an implied contrast between the law of Christ and the law of Moses, as if he said ‘If you desire to keep a law, Christ enjoins on you a law which you can only prefer to all others; and that is, to cherish kindness towards each other. He who lacks this has nothing.’ On the other hand, he says that when everyone compassionately helps his neighbor, the law of Christ is fulfilled.” The law of Christ therefore implies no obligation to the commands at Sinai. If anything, it is a link to the new commandment of John 13:34.
What conclusions can we draw from this data? I offer a few.
- When we see the word “commandment” in Scripture, it does not always equate to law, certainly not the law of Moses. The Lord Jesus gave his disciples a new commandment, that we love one another as he has loved us. Two things we observe. Since it is a new commandment, it was not part of what God previously revealed at Sinai. Love of neighbor, even loving the sojourner was part of the Mosaic code, but loving one’s enemies, dying for those who were at enmity with you—this was nowhere in the Pentateuch. Secondly, it is standard that far exceeds anything we find in the law of Moses. Loving others as Jesus loved us is unprecedented, and it took the cross to reveal this kind of love.
- The law is not a standard Christians are bound to. Because the law as commandment, as treaty document, was given at Sinai only to the seed of Jacob, those who are part of the church, the body of Christ, are not bound to it. The New Testament makes this point repeatedly, though some still want to put Christians under obligation to the Mosaic law. Paul says that to be under the law is to be under sin’s mastery (Rom 6:14) and that we do not walk by the law, but by the Spirit. Paul says Christians have died to the law, and the place we now live (risen, seated at God’s right hand, in the heavenly places with our risen head) is a place where the law does not prevail.
- Those who are in Christ are under a new head, no longer bound to the flesh or to who we were in Adam. The law spoke to the flesh and to those in Adam. We can acknowledge with Paul that the law is holy and righteous and good, even as we acknowledge with the apostle that our life under the headship of Christ means that we have died to the law—both to its curses and commandments. The law still provides wisdom, and is part of God’s revelation in Scripture, so no one should think that it has nothing to teach us, but we need to carefully delineate what the law can, and cannot do in the lives of Spirit-indwelt believers in Jesus.
 Leon Morris, The Epistle to the Romans (Grand Rapids, Eerdmans, 2012), 144
 John Calvin, The Epistles of Paul the Apostle to the Galatians, Ephesians, Philippians and Colossians. Calvin’s Commentaries 11. Edited by David W. Torrance and Thomas F. Torrance. Translated by T. H. L. Parker. (Grand Rapids: Eerdmans, 1965), 110.