Genesis 25:26; Genesis 25:32-34

26 Afterward his brother came forth with his hand holding on to Esau's heel, so his name was called Jacob; and Isaac was sixty years old when she gave birth to them.

32 Esau said, "Behold, I am about to die; so of what use then is the birthright to me?"

33 And Jacob said, "First swear to me"; so he swore to him, and sold his birthright to Jacob.

34 Then Jacob gave Esau bread and lentil stew; and he ate and drank, and rose and went on his way. Thus Esau despised his birthright.