A Commentary by John Stott
makes it indispensable.
Paul now explains the true function of God’s law in relation to His promise by asking and answering two questions.
Question 1: ‘Why then the law?’ (verses 19, 20)
One can almost hear the indignant expostulation of one of the Judaizers, saying something like this: ‘Really, Paul, you are the limit! If it is through faith only that a man is in Christ and becomes a beneficiary of God’s promise to Abraham, what is the point of the law? Your theology so fuses Abraham and Christ, that you squeeze out Moses and the law altogether. There’s no room for the law in your gospel. You wicked, turbulent fellow, your message is akin to blasphemy. You are “teaching men everywhere against…the law”’ (Acts 21:28).
But Paul had his answer ready. The Judaizers misunderstood and misrepresented his position. He was far from declaring the law unnecessary, for he was quite clear that it had an essential part to play in the purpose of God. The function of the law was not to bestow salvation, however, but to convince men of their need of it. To quote Andrew Jukes, ‘Satan would have us to prove ourselves holy by the law, which God gave to prove us sinners.’
The apostle’s own statement of the purpose of the law is given in verse 19: *Why then the law? It is added because of transgressions*. He elaborates this in his Epistle to the Romans: ‘through the law comes knowledge of sin’ (3:20); ‘where there is no law there is no transgression’ (4:15); and ‘if it had not been for the law, I should not have known sin’ (7:7). So the law’s main work was to expose sin. It is the law which turns ‘sin’ into ‘transgression’, showing it up for what it is, a breach of the holy law of God. ‘It is added to make wrongdoing a legal offence’ (verse 19, NEB). It was intended to make plain the sinfulness of sin as a revolt against the will and authority of God. And it was added *till the offspring should come to whom the promise had been made* (verse 19). Thus, the law looked on to Christ, Abraham’s seed, as the Person through whom transgression would be forgiven.
The rest of verse 19 and verse 20 are acknowledged to be difficult. They have been variously interpreted. The apostle is probably emphasizing the inferiority of the law to the gospel. He says that the law ‘was promulgated through angels, and there was an intermediary’ (verse 19b, NEB). The activity of angels in connection with giving of the law is mentioned in Deuteronomy 33:2; Psalm 68:17; Acts 7:53 and Hebrews 2:2 The ‘intermediary’ is doubtless Moses. So when God gave the law He spoke through angels and through Moses. There were two intermediaries – in Lightfoot’s expression, ‘a double interposition, a twofold mediation, between the giver and the recipient’. But when God spoke the gospel to Abraham He did it direct, and that is probably the meaning of the phrase *God is one* (verse 20). We can sum it up in the words of Bishop Stephen Neill, ‘the promise came to Abraham first-hand from God; and the law comes to the people *third-hand* – God – the angels – Moses the mediator – the people’.
Question 2. ‘Is the law then against the promises of God?’ (verses 21,22).
This second question is different from the first in that it seems to be addressed not to Paul by the Judaizers, but to the Judaizers by Paul. He is accusing them of doing just this, of making the law contradict the gospel, the promises of God. Their teaching was: ‘keep the law and you will gain life.’ And they thought they were being practical! Paul denies it. Their position was purely hypothetical: *if a law had been given which could make alive, then righteousness would indeed be by the law* (verse 21). But no such law has been given. Turning from hypothesis to reality, the fact is that nobody has ever kept the law of God. Instead, we sinners break it every day. Therefore the law cannot justify us.
How, then, is it possible to create a harmony between the law and the promise? Only by seeing that men inherit the promise because they cannot keep the law, and that their inability to keep the law makes the promise all the more desirable, indeed indispensable. Verse 22: *The Scripture consigned all things to sin*, for the Old Testament plainly declares the universality of human sin, e.g. ‘there is none that does good, no, not one’ (Ps. 14:3). And Scripture holds every sinner in prison for his sins, in order *that what was promised to faith in Jesus Christ might be given to those who believe*. Luther expresses the matter with his usual forcefulness: ‘The principle point…of the law…is to make men not better but worse; that is to say, it sheweth unto them their sin, that by the knowledge thereof they may be humbled, terrified, bruised and broken, and by this means may be driven to seek grace, and so to come to that blessed Seed (sc. Christ).’
To summarize, the Judaizers held falsely that the law annuls the promise and supersedes it; Paul teaches the true function of the law, which is to confirm the promise and make it indispensable.