Genesis 25:33-34 King James Version (KJV)
33 And Jacob said, Swear to me this day; and he sware unto him: and he sold his birthright unto Jacob.
34 Then Jacob gave Esau bread and pottage of lentiles; and he did eat and drink, and rose up, and went his way: thus Esau despised his birthright.
Genesis 25:33-34 New International Version (NIV)
33 But Jacob said, “Swear to me first.” So he swore an oath to him, selling his birthright to Jacob.
34 Then Jacob gave Esau some bread and some lentil stew. He ate and drank, and then got up and left.
So Esau despised his birthright.