Genesis 25:32-34 NIV

[32] “Look, I am about to die,” Esau said. “What good is the birthright to me?” [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.