Genesis 25:27-31

And the boys grew: and Esau was a skilful hunter, a man of the field; and Jacob was a quiet man, dwelling in tents. Now Isaac loved Esau, because he did eat of his venison: and Rebekah loved Jacob. And Jacob boiled pottage: and Esau came in from the field, and he was faint: and Esau said to Jacob, Feed me, I pray thee, with that same red pottage; for I am faint: therefore was his name called Edom. And Jacob said, Sell me first thy birthright.