(16) Therefore it is of faith.--The words "it is" have to be supplied. "It" stands for the Messianic inheritance, or, in common phrase, salvation. Faith on man's part is correlative with grace on the part of God, and salvation being thus dependent upon grace is as wide and universal as grace itself. It knows no restriction of law.

Not to that only which is of the law.--Not only to that part of the human race which belongs to the dispensation of the Law, but also to that which is in a spiritual sense descended from Abraham by imitating his faith.

Verses 16, 17. - Therefore it is of faith, that it may be according to grace (κατὰ χάριν, as in ver. 4); to the end the promise may be sure to all the seed; not to that only which is of the Law, but to that also which is of the faith of Abraham, who is the father of all, (as it is written, A father of many nations have I made thee,) before him whom he believed, who quickeneth the dead, and calleth the things that are not as though they were. Ver. 16 introduces no new thought, being but a summing up of what has been said, except that, in ver. 17, the text Genesis 17:5 is adduced in support of the extended sense in which "the seed of Abraham" has been understood. In ver. 17, too, the thought is introduced of how Abraham evinced his faith; and this with a view of showing it to have been in essence the same as the justifying faith of Christians.

4:13-22 The promise was made to Abraham long before the law. It points at Christ, and it refers to the promise, Ge 12:3. In Thee shall all families of the earth be blessed. The law worketh wrath, by showing that every transgressor is exposed to the Divine displeasure. As God intended to give men a title to the promised blessings, so he appointed it to be by faith, that it might be wholly of grace, to make it sure to all who were of the like precious faith with Abraham, whether Jews or Gentiles, in all ages. The justification and salvation of sinners, the taking to himself the Gentiles who had not been a people, were a gracious calling of things which are not, as though they were; and this giving a being to things that were not, proves the almighty power of God. The nature and power of Abraham's faith are shown. He believed God's testimony, and looked for the performance of his promise, firmly hoping when the case seemed hopeless. It is weakness of faith, that makes a man lie poring on the difficulties in the way of a promise. Abraham took it not for a point that would admit of argument or debate. Unbelief is at the bottom of all our staggerings at God's promises. The strength of faith appeared in its victory over fears. God honours faith; and great faith honours God. It was imputed to him for righteousness. Faith is a grace that of all others gives glory to God. Faith clearly is the instrument by which we receive the righteousness of God, the redemption which is by Christ; and that which is the instrument whereby we take or receive it, cannot be the thing itself, nor can it be the gift thereby taken and received. Abraham's faith did not justify him by its own merit or value, but as giving him a part in Christ.Therefore it is of faith that it might be by grace,.... Meaning either the promise of being heir of the world, or the inheritance itself, or adoption which gives heirship, or remission of Sin, or the blessing of justification, either and all of these are of faith; not as the cause or condition of them, but as the means of God's fixing and appointing to be the recipient of all and each of them: which is done, "that it might be by grace"; appear to be of the free grace and favour of God, as each of these blessings are: forasmuch as every blessing is received by faith, it is manifest it must be by grace; since faith itself is a gift of God's grace, and lies purely in receiving favours at the hand of God, to whom it gives all the glory of them: and this is done with a further view,

to the end the promise might be sure to all the seed. The promise of the above blessings, particularly of the inheritance which is made in the covenant of grace, ordered in all things and sure, and which could not be disannulled by the law that came after it; this being by faith and of grace, and not of works, nor at all depending upon them, becomes sure to all believers, to all Abraham's spiritual seed:

not to that only which is of the law; to the Jews, who are said to be of the law, in distinction to the Gentiles who were without it; and designs such of them as were believers in Christ, and to whom the Gospel was the power of God unto salvation; to these the promise was, and was sure, and not to them only:

but to that also which is of the faith of Abraham; to the Gentiles, who though they are not by natural descent from Abraham, yet are of the same faith with him, and so are his seed in a spiritual sense:

who is the father of us all; whether Jews or Gentiles, who are Christ's, and so Abraham's spiritual seed, and heirs of eternal life, according to the free promise of grace.