{7} And not only this; but when Rebecca also had conceived by one, even by our father Isaac;

(7) Another strong and persuasive proof taken from the example of Esau and Jacob, who were both born of the same Isaac, who was the son of promise of one mother, and were born at the same time, and not at different times as Ishmael and Isaac were: and yet nonetheless, as Esau was cast off, only Jacob was chosen: and that before their birth, that neither any goodness of Jacob's might be thought to be the cause of his election, neither any wickedness of Esau to be the cause of his casting away.

People's New Testament

9:10 And not only this. The first argument is that the true seed are children of the promise, a spiritual seed rather than of the flesh.

But when Rebecca also had conceived, etc. The second argument, now begun, is that God has the right to reject what nation he will, including the Jews, and to choose other races if he will. This is shown by facts from history. He did exercise the right of choice when he chose Jacob as the chosen nation, instead of Esau. The facts are recited to show this.

Wesley's Notes

9:10 And that God's blessing does not belong to all the descendants of Abraham, appears not only by this instance, but by that of Esau and Jacob, who was chosen to inherit the blessing, before either of them had done good or evil. The apostle mentions this to show, that neither were their ancestors accepted through any merit of their own. That the purpose of God according to election might stand - Whose purpose was, to elect or choose the promised seed. Not of works - Not for any preceding merit in him he chose. But of him that called - Of his own good pleasure who called to that privilege whom he saw good.

Jamieson-Fausset-Brown Bible Commentary

10-13. And not only this; but when Rebecca, &c.-It might be thought that there was a natural reason for preferring the child of Sarah, as being Abraham's true and first wife, both to the child of Hagar, Sarah's maid, and to the children of Keturah, his second wife. But there could be no such reason in the case of Rebecca, Isaac's only wife; for the choice of her son Jacob was the choice of one of two sons by the same mother and of the younger in preference to the elder, and before either of them was born, and consequently before either had done good or evil to be a ground of preference: and all to show that the sole ground of distinction lay in the unconditional choice of God-"not of works, but of Him that calleth."

Matthew Henry's Concise Commentary

9:6-13 The rejection of the Jews by the gospel dispensation, did not break God's promise to the patriarchs. The promises and threatenings shall be fulfilled. Grace does not run in the blood; nor are saving benefits always found with outward church privileges. Not only some of Abraham's seed were chosen, and others not, but God therein wrought according to the counsel of his own will. God foresaw both Esau and Jacob as born in sin, by nature children of wrath even as others. If left to themselves they would have continued in sin through life; but for wise and holy reasons, not made known to us, he purposed to change Jacob's heart, and to leave Esau to his perverseness. This instance of Esau and Jacob throws light upon the Divine conduct to the fallen race of man. The whole Scripture shows the difference between the professed Christian and the real believer. Outward privileges are bestowed on many who are not the children of God. There is, however, full encouragement to diligent use of the means of grace which God has appointed.