No single verse of Scripture gives a complete picture of the Christian’s relationship to the law. One has to read the whole of the New Testament to come up with a coherent picture of how the law of Moses may (or may not) relate to the believer in Christ. But without question, the apostle Paul has more to say about the law than any other writer, and one of the things he’s careful to say is that Christian’s do not keep the law of Moses. Many will raise an objection at this point, and say “Of course he did! Look at what he said to the Romans, to the Ephesians!” The first of these passages is Romans 13:8-10:
“Owe no one anything, except to love each other, for the one who loves another has fulfilled the law. For the commandments, “You shall not commit adultery, You shall not murder, You shall not steal, You shall not covet,” and any other commandment, are summed up in this word: “You shall love your neighbor as yourself.” Love does no wrong to a neighbor; therefore love is the fulfilling of the law.”
Look carefully at what he says here. Is there any injunction to “keep the law”? Is there any order that believers must keep the commandments? Rather, he stresses fulfillment of the law, and that the means of doing so is by love. These few commands that Paul cites from the Decalogue are not incongruous with what believers are called to be and to do, but Paul never measures our maturity in Christ or our conformity to Jesus by the Mosaic law. Earlier in the epistle, Paul wrote: “By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit.” Rom 8:3-4. Here, too, it is the law fulfilled not kept that Paul speaks of. As he consistently does, Paul links the law with the flesh (and the weakness of it.) The righteous requirement of the law is holiness, and holiness is fulfilled in the believer when we walk by the Spirit, in conformity to Christ, never by striving to keep the law.
Think for a moment of the carnival game one sometimes sees called “high striker.” You swing a large mallet and hit a plunger. If you whack it hard enough, you ring the bell at the top of the tower. If hitting the bell is 100, then you go past 80 on your way up. This is similar to the law. The commands of Decalogue are not inconsistent or at odds with what believers strive after, but they don’t go far enough.
When saying that Christian holiness is not measured by the Mosaic law, I sometimes hear an objection that Christ kept the whole law, and that if we are to imitate Christ, we, too, will keep the law. This is a single-faceted, and indeed a shallow view of what the Lord accomplished in his earthly life and in his death. Jesus did far more than keep the law, and he called believers to go beyond it as well. Whereas the law said “love your neighbor as yourself,” Jesus said “love one another as I have loved you”—a decidedly higher standard. To insist that since Jesus kept the Mosaic law we should too also discounts the repeated statements in the New Testament that we can’t keep the law.
The other passage, in Ephesians 6, also seems to say we should keep the law. “Children, obey your parents in the Lord, for this is right. ‘Honor your father and mother’ (this is the first commandment with a promise), ‘that it may go well with you and that you may live long in the land.’ Fathers, do not provoke your children to anger, but bring them up in the discipline and instruction of the Lord.” Eph 6:1-4
Note that Paul starts not with the 5th commandment, but with his own apostolic instruction: Obey your parents in the Lord, for this is right. He then cites the 5th commandment as an example of what I previously noted: The law is not incongruous with Christian holiness, but it’s not the full extent of it, (though most people end the citation there.) Paul goes on to provide instruction (and an imperative) to fathers. Was a prohibition on inciting anger in children part of the Mosaic law? It was not, but Paul has moved on from law to love. Consistent with what he said in Romans 13, too. A hallmark of Paul’s doctrine is that he does not believe Christians need the law to walk as they should. His own apostolic, and Spirit-inspired commands are sufficient. Brian S. Rosner summarizes this well:
“Paul never says, as he does of Jews, that believers in Christ rely on the law, boast about the law, know God’s will through the law, are educated in the law, have light, knowledge and truth because of the law, do, observe, keep the law, on occasion transgress the law, or possess the law as letter or a written code, as a book, as decrees, or as commandments.”
To be free from obligation to the Mosaic law is not to say that Christians have no standard, or do not pursue Christlikeness. On the contrary, they have all they need in the gospel and the teaching of the Lord’s chosen apostles. But these things are not the same as the law of Moses.
Is this an artificial distinction? Is it just word games to say that Paul emphasizes fulfilling the law, but not keeping it? It is not. Think of the carnival game example again. If I hit with enough force to get up to 70, I don’t make it to 100. If I strive but to keep the law, I will not love. If I love, I will fulfill the law. Stated differently, “love is the fulfilling of the law.” But Scripture never says “Keeping the law is the fulfilling of love.”
 Brian S. Rosner, Paul and the Law: Keeping the Commandments of God (Downers Grove, IVP Academic, 2013), 221