After the brothers are grown, true to their nature in the womb, they continue to be divided as one is careless and the other is shrewd in a disrespectful transaction over the birthright. Impulsively, Jacob asks for the birthright from Esau, and over a simple meal, Esau throws it to the wind.
Additional scripture: Hebrews 12:14-17, 25, 28-29, and Exodus 20:18-21