As it is written, Jacob have I loved, but Esau have I hated.

People's New Testament

9:13 As it is written. In Mal 1:2,3. The language of Malachi, in its connection, shows that this is spoken of the two races: 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.

Wesley's Notes

9:13 As it is written - With which word in Genesis, spoken so long before, that of Malachi agrees. I have loved Jacob - With a peculiar love; that is, the Israelites, the posterity of Jacob. And I have, comparatively, hated Esau - That is, the Edomites, the posterity of Esau. But observe, This does not relate to the person of Jacob or Esau Nor does it relate to the eternal state either of them or their posterity. Thus far the apostle has been proving his proposition, namely, that the exclusion of a great part of the seed of Abraham, yea, and of Isaac, from the special promises of God, was so far from being impossible, that, according to the scriptures themselves, it had actually happened. He now introduces and refutes an objection. Mal 1:2,3.

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.