For if the inheritance depends on the law, then it no longer depends on a promise; but God freely granted it to Abraham through a promise.
18. If the inheritance be of the law. His opponents might still reply, that nothing was farther from their intention than to weaken or disannul God’s covenant. To deprive them of every kind of subterfuge, he comes forward with the assertion, that salvation by the law, and salvation by the promise of God, are wholly inconsistent with each other.
The apostle having reproved the Galatians for not obeying the truth, and endeavoured to impress them with a sense of their folly herein, in these verses he largely proves the doctrine which he had reproved them for rejecting, namely, that of justification by faith without the works of the law. This he does several ways. I. From the example of Abraham's justification. This argument the apostle uses, Rom. 4.
Commenting on Galatians 3:6-18
For if the inheritance be of the law,.... By the inheritance is meant, either the eternal inheritance, everlasting life and happiness in heaven, which is the gift of God through Christ, and not attained to and enforced by the works of the law; or particularly the blessing of justification, promised in the covenant to Abraham, and his spiritual seed; even to the Gentiles, and inherited...