(Verse 30) And Esau said to Jacob: Give me a taste of that red stew, for I am famished. That is why he was called Edom. Red or tawny is called Edom in the Hebrew language. Therefore, from the fact that he sold his birthright for red food, he obtained the name Edom, which means tawny.
Let frugality be joined to fasting. Just as overeating is to be censured, so stimulants of the appetite must be eliminated. It is not that certain kinds of food are to be detested but that bodily pleasure is to be checked. Esau was censured not for having desired a fat calf or plump birds but for having coveted a dish of lentils.
The longer I looked into it the more I came to suspect that I was perceiving a universal law... It may be stated as follows: every preference of a small good to a great, or a partial good to a total good, involves the loss of the small or partial good for which the sacrifice was made.
Apparently the world is made that way. If Esau really got the pottage in return for his birthright, then Esau was a lucky exception. You can't get second things by putting them first; you can get second things only by putting first things first. From which it would follow that the question, What things are first? is of concern not only to philosophers but to everyone.
[AD 420] Jerome on Genesis 25:30