The law and the gospel are two parts of the Word of God; both are useful for our salvation and spiritual life. The two aspects of Scripture should be clearly distinguished from each other, otherwise much confusion will result. Yet the law and gospel are so intimately related that an accurate knowledge of one cannot be obtained without the other. The gospel will be rendered meaningless if we do not understand the justice and wrath of God revealed in his law. The cross is as much a manifestation of God’s justice as it is of his mercy.

The law comprises everything in scripture in the form of divine command and prohibition, whereas the gospel is the accomplishment and application of redemption. The distinction between law and gospel is not the same as that between the Old and New Testaments. There is law and gospel in both Testaments, albeit the law is more prominent in the Old while the gospel is more fully revealed in the New.

God gave the law to his people Israel by Moses. The Ten Commandments, or the Decalogue, are the summary of the Mosaic Law, but we should keep in mind that there were hundreds of other rules and precepts that regulated the moral, religious and civil life of Israel.

The moral commandments (prohibiting idolatry, blasphemy, disobedience, stealing, lying, murder, coveting, etc) are applicable in all ages, including our own. The writers of the New Testament reiterate the moral laws for Christians.

The ceremonial laws, such as various feasts and Sabbaths, and the priestly sacrifices of animals, have been abrogated because they were fulfilled in Christ (see Col 2:16,17; Heb 10). As Christians we do not observe the Jewish Sabbath and its ceremonies. However the New Testament commands Christians to gather together, and following the apostolic example (Act 20:7; 1 Cor 16:2), the churches meet on the first day of the week, the day of the resurrection, to worship the Lord. This is called the Lord’s Day or the Christian Sabbath.

It is customary to distinguish a three-fold use of the law.

The law serves the purpose of restraining disorder and injustice, and promoting fairness. Human society cannot survive without law and its enforcement. The civil laws of Israel are not applicable to the church since the people of God are no longer organized as a single nation. Nonetheless Christians are admonished to obey the civil authorities of their individual countries (see Rom 13).

The law cannot save, yet it is indispensable in evangelism. It convicts us of sin, our inability to meet its strict demands, and our dire need of a Saviour.

All are aware of God’s moral law, even those who never heard the Ten Commandments, since our conscience tells us what is right and wrong (Rom 2:14, 15). No one can be excused on the basis of ignorance. Some are more responsible than others because they have more light, but all are accountable for the light they have.

Moreover the entire human race is guilty of transgressing the law. ‘Now we know that whatever the law says, it says to those who are under the law, that every mouth may be stopped, and all the world may become guilty before God’ (Rom 3:19). Even a cursory look at the Ten Commandments suffices to convict us that we have missed the mark. Did I always speak the truth and obey my parents? Was I always pure and honest (Jesus says that lust is adultery in the heart)? Was I ever unjustly angry (Jesus says that anger is the seed of murder)? Did I always give God the honour and praise he deserves? Indeed, we are all ‘guilty before God’.

When a sinner looks at himself in the law as in a mirror, he sees the darkness and filth of his heart, but that is as far as the law can take him. It cannot cleanse nor excuse the sinner. The law compels the convicted sinner to seek forgiveness elsewhere. ‘Therefore the law was our tutor to bring us to Christ, that we might be justified by faith’ (Gal 3:24). Thus the law works along the gospel in the conversion and salvation of sinners.

The law of God is the ethical norm for believers. The law does not save, but it is our guide to live as children of God, as he had promised, ‘I will put My Spirit within you and cause you to walk in My statutes, and you will keep My judgments and do them’ (Ez 36:27).

The first Psalm describes the blessed man who does not walk in the counsel of the ungodly but finds joy and meditates in the law of God. The apostle Paul gives his personal testimony, saying, ‘I delight in the law of God according to the inward man’ (Rom 7:22). Elsewhere he summarizes our Christian duty by a single word, love, and goes on to explain that love is the fulfillment of the law (Romans 13:8-10).

We need the law to discern God’s will, our remaining sins and weaknesses, and our continual need for grace, pardon and the power of the Spirit for our sanctification.

There are two great enemies of the law and the gospel, antinomianism and legalism. Both are deadly errors and we must be careful not to fall into any one of them.

1. Antinomianism (literally ‘against the law’) refers to the false idea that the gospel frees Christians from required obedience to any law. Sadly antinomianism is not uncommon among evangelicals. The Bible warns against this deception, ‘He who says, I know Him, and does not keep His commandments, is a liar, and the truth is not in him’ (1 John 2:4). Jesus did not come to destroy the law, but to fulfill it. Not the smallest letter will by any means disappear from the law, he said, and solemnly warned those who break the least of the commandments and teach others to do so (see Matt 5:17-19).

As Christians we rejoice that we are not under the law, in the sense that God has been gracious to us and we are no longer under its condemnation. However Christian freedom is not lawlessness! Paul continues to say that we become willing slaves of righteousness (Rom 6:14-23). We remain under obligation, indeed we are now motivated by love, to obey Christ’s commandments (John 14:21). For the first time we have been set free from the bondage of sin to serve and obey the living God. Our obedience, through imperfect, is a powerful witness of God’s saving work in us. ‘I will put My laws into their hearts, and in their minds I will write them’ (Hebrews 10: 16, 17). God forgives; he also gives his children an obedient heart.

2. Legalism is the false doctrine that salvation can be gained by our obedience to the law. This attitude is common among Roman Catholics. Legalism is an impossible task. We are all law-breakers; therefore the law cannot justify anyone. ‘Therefore by the deeds of the law no flesh will be justified in His sight, for by the law is the knowledge of sin’ (Rom 3:20). In fact, all those who hope to attain life through obedience of the law are condemned. ‘Cursed is everyone who does not continue in all things which are written in the book of the law, to do them’ (Gal 3:10). God’s law makes no concessions but demands perfect and unbroken obedience. It is foolish for sinners to hope in that very thing that condemns them.