On the same random thought, as the people were scattered during the uprising of Babel, does it necessarily mean that only the Jews (or the forerunners of the Jews) were the ones who kept the word and knowledge of God?
It seems not, because in a classic foreshadowing, the King of Salem took bread and wine, the Holy Sacraments and blessed Abraham in the name of the Lord. And Abraham gave him his ten percent, acknowledging him as a priest of God.
Gen 14:18And Melchizedek, king of Salem, the priest of the Most High God, took bread and wine,
What made Jacob any better than Esau?
The fact that he desperately wanted the blessings of God for the firstborn whilst Esau saw it as nothing?
Esau didn't have to sell his birthright. Even if Jacob refused to feed him, he could have gone to any of the other tents in Isaac's settlement. Any one of them would go out of their way to do a favour for the obvious heir. Why not? When he got into power, he would have his favourites, wouldn't he? Why not wriggle their way into his favour now in anticipation?
But Esau didn't think of the future. He thought only of his hunger in the now.
In a time where birthright determined your status and all that you would ever have in life, he threw it away for bread and bean stew. How silly.
Gen 25:34Jacob then gave Esau some bread and some of the bean stew, and when Esau had finished eating and drinking, he just got up and left, showing how little he thought of his rights as the first-born.