And not only, etc. There are in this chapter some broken sentences, such as this is, -- But Rebecca also, who had conceived by one, our father Isaac; for he leaves off in the middle, before he comes to the principal verb. The meaning, however, is, that the difference as to the possession of the promise may not only be seen in the children of Abraham, but that there is a much more evident example in Jacob and Esau: for in the former instance some might allege that their condition was unequal, the one being the son of an handmaid; but these were of the same mother, and were even twins: yet one was rejected, and the other was chosen by the Lord. It is hence clear, that the fulfilment of the promise does not take place in all the children of the flesh indiscriminately. And as Paul refers to the persons to whom God made known his purpose, I prefer to regard a masculine pronoun to be understood, rather than a neuter, as Erasmus has done: for the meaning is, that God's special election had not been revealed only to Abraham, but also to Rebecca, when she brought forth her twins. [1]

Footnotes

1 - Here is a striking instance of a difficulty as to the construction, while the meaning of the whole passage is quite evident. The ellipsis has been variously supplied; "and not only this," i.e., what I have stated; "and not only he," i.e., Abraham to whom the first communication was made; "and not only she," i.e., Sarah, mentioned in the preceding verse; "but Rebecca also is another instance." But it may be thus supplied, -- "and not only so," i.e., as to the word of promise; "but Rebecca also had a word," or a message conveyed to her. That the verse has a distinct meaning in itself is evident, for the next begins with a gar, "for;" and to include Romans 9:11, in a parenthesis, seems by no means satisfactory. The three verses may be thus rendered, -- 10. And not only so, but Rebecca also received a message, when she conceived by the first, (i.e., son or seed,) even our father Isaac: 11. for they being not yet born, and having not done any good or evil, that the purpose of God according to election might stand, not 12. through works, but through him who calls, it was said to her, "The elder shall serve the younger." The words ex henos, rendered commonly "by one," have never been satisfactorily accounted for. It. seems to be an instance of Hebraism; the word 'chd, "one," means also "first." We have other instances of this in the New Testament; eis mian ton sabbaton -- "on the first (i.e., day) of the week," Matthew 28:1; see also Mark 16:2; John 20:19. "The first day" in Genesis 1:5, is rendered by the Septuagint, hemera mia. Isaac was the first son or seed of promise: and a difference was made in the children of the very first seed. But this meaning of eis is said by Schleusner to be sanctioned by Greek writers, such as Herodotus and Thucydides There is no necessity of introducing the word "children," at the beginning of Romans 9:11; the antecedent in this case, as it sometimes happens, comes after the pronoun; and it is the "elder" and "younger" at the end of Romans 9:12. -- Ed.

And not only this - Not only is the principle of making a distinction among the natural descendants of Abraham thus settled by the promise, but it is still further seen and illustrated in the birth of the two sons of Isaac. He had shown that the principle of thus making a distinction among the posterity of Abraham was recognised in the original promise, thus proving that all the descendants of Abraham were not of course to be saved; and he now proceeds to show that the principle was recognised in the case of his posterity in the family of Isaac. And he shows that it is not according to any natural principles that the selection was made; that he not only made a distinction between Jacob and Esau, but that he did it according to his good pleasure, choosing the younger to be the object of his favor, and rejecting the older, who, according to the custom of the times, was supposed to be entitled to special honor and rights. And in order to prove that this was done according to his own pleasure, he shows that the distinction was made before they were born; before they had formed any character; and, consequently, in such a way that it could not be pretended that it was in consequence of any works which they had performed.
But when Rebecca - The wife of Isaac; see Genesis 25:21, Genesis 25:23.

And not only this - A Jew might object: "Ishmael was rejected, not by the sovereign will of God, but because he was the son of the handmaid, or bond-woman, and therefore unworthy to be the peculiar seed; but observe, this was not the only limitation of the seed of Abraham with regard to inheriting the promise, for when Rebecca was with child by that one person of Abraham's issue to whom the promise was made, namely, our father Isaac, she went to inquire of the Lord, Genesis 25:22, Genesis 25:23 : And the Lord said unto her, Two nations are in thy womb, and two manner of People shall be separated from thy bowels; and the one People shall be stronger than the other People; and the elder shall serve the younger. That is, the posterity of the younger shall be a nation much more prosperous and happy than the posterity of the elder.

(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.

And not only this,.... This instance of Ishmael and Isaac, is not the only one, proving that Abraham's natural seed, the children of the flesh, are not all children, the children of God:
but when Rebecca also had conceived by one, even by our father Isaac, "it was said unto her", Romans 9:12, being in a parenthesis, "the elder shall serve the younger". The apostle was aware, that the Jews would be ready to say, that the instance of Ishmael and Isaac was not a pertinent one; since Ishmael was not born of Sarah, the lawful wife of Abraham, but of a bondwoman, which was the reason his rejection, when Isaac was the son of promise, by the lawful wife, and that they were children of Abraham in the line of Isaac, and so children of the promise, as he was: wherefore he proceeds to mention the case of Jacob and Esau, which was not liable to any such exception; seeing they not only had the same father, but the same mother, Isaac's lawful wife; they were conceived by Rebecca at once, were in the same womb together, were twins, and if any had the preference and advantage, Esau had it, being born first; and yet a difference was made between these two by God himself, and which was notified by him to the mother of them, before either were born.

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."

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. 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.
For the children. The children, yet unborn, were both Isaac's seed according to the flesh; hence, according to the flesh, of the promised seed, and both equally without works, neither having done good nor evil.
That the purpose of God according to election might stand. That it might stand forth that he made the choice of his own will, freely. Of his own will he chose Jacob, yet unborn, to become the head of the chosen race, rather than Esau. Note that this election was not to eternal salvation, but to become the head of a people. As Moses, Samuel, and John the Baptist were raised up for a great work of God, so was Jacob.
It was said unto her, The elder shall serve the younger. See Genesis 25:23. It was said to Rebecca, "Two nations are in thy womb, . . . one people shall be stronger than the other, and the elder (people) shall serve the younger" Esau never served Jacob, but the Edomites, descended from Jacob, served the Israelites. The election here is that of a race.
As it is written. In Malachi 1:2-3. The language of Malachi, in its connection, shows that this is spoken of the two races. Malachi 1:3 says, "I hated Esau and laid waste his mountains and his heritage." This was not true of Esau as a person, but was true of his descendants. One race was loved and the other race hated. God has then asserted his right to freely choose or to reject races. There is not the slightest hint of electing some persons to eternal salvation and others to damnation.

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.