Why did Esau care so much about Isaac’s blessing but not about the birthright?

Esau valued Isaac’s blessing because it represented the double portion of the material estate—the financial inheritance. The birthright, by contrast, meant nothing to him and caused no hard feelings or enmity, so he was not troubled when Jacob obtained it.

Les teaches that the blessing was the double portion of the material estate, and that is why Esau was really interested in this one. The birthright did not bother him or cause any turmoil. From the time they were 24 until they were 77 years of age, there was no enmity and no hard feelings over the birthright, because it did not mean a thing to Esau. But the blessing was something different—it was getting into their pocketbook. So after Jacob had received the blessing and had scarce gone out from Isaac’s presence, Esau came in from his hunting.

Genesis 27

Why was there no enmity between Jacob and Esau before the stolen blessing?

There was no enmity before the stolen blessing because the birthright meant nothing to Esau. From age 24 to 77 there was no turmoil or hard feelings over it. The blessing, however, involved the material estate, and that is what sparked conflict.