7 The real children of Abraham, then, are those who put their faith in God. 8 What's more, the Scriptures looked forward to this time when God would declare the Gentiles to be righteous because of their faith. God proclaimed this good news to Abraham long ago when he said, "All nations will be blessed through you."
Matthew Henry's Commentary on Galatians 3:7-8
Commentary on Galatians 3:6-14
(Read Galatians 3:6-14)
The apostle proves the doctrine he had blamed the Galatians for rejecting; namely, that of justification by faith without the works of the law. This he does from the example of Abraham, whose faith fastened upon the word and promise of God, and upon his believing he was owned and accepted of God as a righteous man. The Scripture is said to foresee, because the Holy Spirit that indited the Scripture did foresee. Through faith in the promise of God he was blessed; and it is only in the same way that others obtain this privilege. Let us then study the object, nature, and effects of Abraham's faith; for who can in any other way escape the curse of the holy law? The curse is against all sinners, therefore against all men; for all have sinned, and are become guilty before God: and if, as transgressors of the law, we are under its curse, it must be vain to look for justification by it. Those only are just or righteous who are freed from death and wrath, and restored into a state of life in the favour of God; and it is only through faith that persons become righteous. Thus we see that justification by faith is no new doctrine, but was taught in the church of God, long before the times of the gospel. It is, in truth, the only way wherein any sinners ever were, or can be justified. Though deliverance is not to be expected from the law, there is a way open to escape the curse, and regain the favour of God, namely, through faith in Christ. Christ redeemed us from the curse of the law; being made sin, or a sin-offering, for us, he was made a curse for us; not separated from God, but laid for a time under the Divine punishment. The heavy sufferings of the Son of God, more loudly warn sinners to flee from the wrath to come, than all the curses of the law; for how can God spare any man who remains under sin, seeing that he spared not his own Son, when our sins were charged upon him? Yet at the same time, Christ, as from the cross, freely invites sinners to take refuge in him.