Genesis 25:29-34

29Once when Jacob was cooking stew, Esau came in from the field, and he was exhausted. 30And Esau said to Jacob, “Let me eat some of that red stew, for I am exhausted!” (Therefore his name was called Edom.) 31Jacob said, “Sell me your birthright now.” 32Esau said, “I am about to die; of what use is a birthright to me?” 33Jacob said, “Swear to me now.” So he swore to him and sold his birthright to Jacob. 34Then Jacob gave Esau bread and lentil stew, and he ate and drank and rose and went his way. Thus Esau despised his birthright.