The law and the gospel are both revealed in the pages of Scripture—in both the Old and the New Testaments. Simply defined, the law is the revelation of God’s standard for holiness and righteousness. In it, God communicates what He requires of human beings if we are going to be in right relationship with Him and inherit eternal life. The law summons us to love and honor God with all our heart, soul, mind, and strength— and to love our neighbor as ourselves. The law requires complete and perfect obedience. Since every person has failed to keep the law, it is impossible to earn eternal life through it. The gospel, on the other hand, is the message about what Jesus has done for us, in our place, to accomplish our salvation. It is the message of God’s salvation that He has worked through His Son that is grounded completely in His grace and is applied to sinners by faith apart from works. The gospel is entirely about Jesus and what He did, not about what we must do.
The distinction then between law and gospel can be summarized as follows:
The law reveals the standard of righteousness, the demands of God’s just character required to please and honor Him, yet provides no power whatsoever to meet the standard it reveals. The gospel, in contrast, actually contains nothing whatsoever in it for us to do to earn or keep God’s favor or forgiveness. Rather, it is gloriously good news, a free gift that we simply receive by grace through faith. In this sense, in terms of saving and sanctifying power, the law demands everything and gives nothing; the gospel demands nothing and gives everything.
The law of God is holy and has three biblical purposes:
The first purpose of the law is to be a mirror, as it reflects the perfect righteousness of God, and also illuminates human sinfulness. The law acts as a severe schoolmaster, highlighting our weakness so that we might seek the grace found only in Christ who fulfilled the law on our behalf. The second purpose of the law is the restraint of evil. The law cannot change human hearts. It can, however, serve to protect the righteous from the unjust, which allows for a limited measure of justice on this earth, until the final day of judgment. The third purpose of the law is to reveal what is pleasing to God. As born-again children of God, we delight in the law as God Himself delights in it. This is the highest function of the law, to serve as an instrument for the church to glorify God by showing us what pleases Him. If we confuse the categories of law and gospel, we end up effectively losing both.
An improper understanding of law and gospel leads us to soft-pedal the law. If we think that our own efforts to keep the law, in any way, to any extent, are a part of the righteousness that justifies us before God, we are mistaken. Sinners attempt to lower God’s standards by relativizing the law and lowering its requirements so they can actually keep it! In doing so, however, the law is gutted of its holiness, goodness, and glory. An improper understanding of law and gospel also results in our turning the gospel into a covenant of works, where the gospel becomes a covenant in which we earn righteousness before God through our obedience. The gospel is made to sound hard. All of this results in the saints being robbed of the peace and rest that is ours in Christ.
(Galatians 3:1-9, 15-26, Philippians 3:3-11, 1 Timothy 1:3-11, Romans 7:1-6)