What was the spiritual significance of the birthright in a biblical family?
The birthright represented the spiritual side of the family position. The eldest son was more or less the family priest and spiritual leader. In Abraham's line it was more than that: the promised Messiah and Redeemer would come through this line, making God's sovereign will all-important.
Les explains that the birthright was the spiritual side of the family position. The eldest son was more or less the priest of the family, the spiritual leader. In the little family coming out of Abraham, it was more than being the family priest: through this line the promised Messiah and Redeemer would come. This made it all-important that God's sovereign will be accomplished. Esau, being born first, could have been in the line of the Messiah, but he canceled it because of his no faith, and it fell to Jacob. Jacob got the birthright, not really by deceiving Esau. Les also notes that in the ancient Middle Eastern world, even pagan kings' decrees stood without changing, and Isaac's decree gave Jacob the blessing.