1 Then Isaac called Jacob and blessed him, and charged him, and said to him: “You shall not take a wife from the daughters of Canaan.
2 Arise, go to Padan Aram, to the house of Bethuel your mother’s father; and take yourself a wife from there of the daughters of Laban your mother’s brother.
3 “May God Almighty bless you, and make you fruitful and multiply you, that you may be an assembly of peoples;
4 And give you the blessing of Abraham, to you and your descendants with you, that you may inherit the land in which you are a stranger, which God gave to Abraham.”
5 So Isaac sent Jacob away, and he went to Padan Aram, to Laban the son of Bethuel the Syrian, the brother of Rebekah, the mother of Jacob and Esau.
6 Esau saw that Isaac had blessed Jacob and sent him away to Padan Aram to take himself a wife from there, and that as he blessed him he gave him a charge, saying, “You shall not take a wife from the daughters of Canaan,”
7 and that Jacob had obeyed his father and his mother and had gone to Padan Aram.
8 Also Esau saw that the daughters of Canaan did not please his father Isaac.
9 So Esau went to Ishmael and took Mahalath the daughter of Ishmael, Abraham’s son, the sister of Nebajoth, to be his wife in addition to the wives he had.
Rebekah’s counsel quickly convinced Isaac, still shaken from the recent events, and no longer in any mood to try to delay or thwart God’s purposes. He called Jacob, and gave him strict instruction not to marry a Canaanite woman, almost in the same words that Abraham had used long ago concerning his own marriage (Genesis 24:3). Rather, he was to go back to Rebekah’s family in Padan-aram, and there take a wife from among his own cousins, the daughters of his mother’s brother.
Then, in order that neither Rebekah nor Jacob could have any more doubt that he now fully desired and intended that Jacob should have the full blessing, Isaac repeated the blessing in terms much more like those which he himself had received from God (Genesis 26:3-5).
That is, he specifically invoked on Jacob the blessing of Abraham, as well as the promise that he would be the father of a great multitude, and his seed would possess the land of promise. — Morris, pages 443-444.
The fact that Isaac had sent Jacob far away to find a wife from Rebekah’s people emphasized to Esau that his father, as well as his mother, was highly displeased with Esau’s choice of wives. In a belated attempt to partially correct this situation, Esau went to the home of his Uncle Ismael (Ishmael himself was already dead at this time) and secured one of his daughters, Mahalath (probably the same as Bashemath in Genesis 36:3), as another wife. … Esau made a desperate attempt to regain the favor of his parents and of God. But even in this attempt, he still was wrong, because Ishmael and his descendants had already been cast out by God, so far as the national promises were concerned. — Morris, page 444.