Justification, then, is not of works: else man might boast of himself, instead of God being glorified. It is really according to grace, and not debt; and God reserves his prerogative of justifying the ungodly. Thus God and man have their due place; and as Abraham illustrated the principle, so David speaks of the pronouncing a blessing after this sort in Psa. 32 nothing but imputing righteousness without works could avail for the justifying of a sinner. Nor this only; for the very man, with whom circumcision began as the command of God, was expressly justified by faith before he was circumcised. So manifestly did God order all in his wisdom and goodness that circumcision should be but a seal of the righteousness of faith which Abraham had while yet uncircumcised. Thus the gentiles or the uncircumcised were especially provided for in the unquestionable facts recorded in the first book of the Pentateuch, as no Jew could deny. Abraham was father of all believers in a state like his own, and father of circumcision (i.e., separation to God, couched under that act which set forth mortification of the flesh) not only to the circumcised, but also to those that walk in the footsteps of the faith the ancestor of Israel had before circumcision. Believers from among the gentiles were thus as truly circumcised in the highest sense as Jewish ones
“For not by law was the promise to Abraham or to his seed, that he should be heir of [the] world, but by righteousness of faith. For if those of law [be] heirs, faith is made vain and the promise is annulled.” (Ver. 13, 14.)
The apostle now reasons from the necessary principle of God's promise. This excludes law and supposes faith-righteousness. For evidently law supposes the obedience of man as the condition of receiving the boon which is in question. It was not so in God's dealings with Abraham or his seed. There was not a word about His law when God gave promise to Abraham in Gen. 12, and to his seed in Gen. 22 The promise implies God's fulfillment of it; the law claimed man's obedience of its demands. They are thus, while each is admirable for its own end, absolutely different and mutually exclusive. The promised inheritance is not by law but by another sort of righteousness. It was annexed to faith; and this is so true, that if those who stand on law are heirs, no room is left for faith and the promise comes thus to naught. “For the law worketh out wrath; but where no law is, there is no transgression.” (Ver. 15.) The application is as clear as it is momentous, and this positively as well as negatively. The thing law generally, and in particular the law of God given by Moses, provokes by its very excellence the hostile self-will of man, and so detects his enmity and works out wrath in result. On the other hand, where there is no law, there is no transgression. It is no question of sin here, but of violating positive prescription, which latter of course could not be till the lawgiver uttered the enactments definitely. Then as law existed, it could be transgressed. But it was not yet promulgated in the time of Abraham, who had that wholly different thing—the promise.
The conclusion is, that as law would have defeated the promise of God and brought wrath on man, instead of the inheritance, “on this account [it is] of faith, that [it might be] according to grace in order to the promise being sure to all the seed, not only to that which is of law, but also to that which is of Abraham's faith, who is father of us all (even as it is written, A father of many nations I have made thee), before God whom he believed, that quickeneth the dead and calleth the things that are not as if they are; who against hope believed in hope, in order to his becoming father of many nations according to that which was spoken, So shall be thy seed.” (Ver. 16.-18.) As faith is opposed to works, so is grace to law; while the grace of God who gave the promise makes the sole and withal the large door of faith to open for Gentiles no less than Jews. Had law been the principle, Israel who boasted of possessing the law, though blind to their breaches of it and to their own enhanced exposure to wrath, could alone have made an effort, however vainly. But grace goes out to the Gentile no less than to the Jew who could hardly limit Abraham's paternity of “many nations” to his own people.
Here too another point of great value is noticed. The God whom Abraham believed quickens the dead and calls things that have no being as though they had. This was rendered evident not only by the fact that Sarah bore no child to Abraham, but by their great age when the promise was given. They were as good as dead, and a child of theirs had no existence. But what of all this to God? Long before the time God spoke, Abraham against hope believed in hope. What a pattern of faith! On the human side all was hopeless; on God's part there was simply His word. But Abraham believed, hoped, and was not ashamed. God could not fail to make good what He said “So shall be thy seed.”