Genesis 25:20-28

20And Isaac was forty years old when he took Rebekah to wife, the daughter of Bethuel the Syrian of Padan–aram, the sister to Laban the Syrian. 21And Isaac intreated Yhwh for his wife, because she was barren: And Yhwh was intreated of him, and Rebekah his wife conceived. 22And the children struggled together within her; and she said, If it be so, why am I thus? And she went to enquire of Yhwh. 23And Yhwh 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.

24And when her days to be delivered were fulfilled, behold, there were twins in her womb. 25And the first came out red, all over like an hairy garment; and they called his name Esau. 26And after that came his brother out, and his hand took hold on Esau’s heel; and his name was called Jacob: and Isaac was threescore years old when she bare them. 27And the boys grew: and Esau was a cunning hunter, a man of the field; and Jacob was a plain man, dwelling in tents. 28And Isaac loved Esau, because he did eat of his venison: but Rebekah loved Jacob.1