Genesis 25:32-34

32Esau said, ‘Look, I am so hungry that I will die. Then my birthright will not help me at all!’

33Jacob said, ‘First, make a serious promise to me.’ So Esau promised to sell his birthright to Jacob.

34Then Jacob gave Esau some bread and the soup made from grains. Esau ate the food and he drank. Then he got up and he left. In that way, Esau showed that he did not think that his birthright was important.