Answer
When twins Jacob and Esau were born, Esau came first, technically making him the firstborn. As the firstborn son, Esau automatically held the “birthright.” A birthright was an honor given to the firstborn, bestowing “head of household” status and the right to inherit his father’s estate. The son with the birthright would receive a double portion of whatever was passed down (see Deuteronomy 21:17). Yet, even before the twins were born, the Lord predicted that Esau would serve Jacob (Genesis 25:23).
Later in Genesis 25, Esau sold his birthright, giving it up for a meal because he was hungry. “Thus Esau despised his birthright” (Genesis 25:29-35). When the time came for Isaac to bless his sons, Jacob deceived his father into giving him Esau’s blessing instead (Genesis 27).
A blessing could be given regardless of birthright. However, a greater blessing was given to the one who held the birthright. After Jacob’s deception, Esau complained that “he took my birthright, and now he’s taken my blessing!” (Genesis 27:36). Esau begged his father for some type of blessing to be given to him, and he did receive a secondary, inferior blessing (verses 38-40).
An interesting parallel took place later in the life of Jacob. Jacob’s son Joseph had two sons, Ephraim and Manasseh. Manasseh was the elder son and should have had the birthright. But when Jacob bestowed his blessing upon his grandsons, he crossed his hands, much to Joseph’s surprise, placing his right hand on the younger son. In this way, Ephraim, the younger son, received the greater blessing (Genesis 48).
In Genesis 49, Jacob gave blessings to each of his 12 sons. Reuben, the firstborn, had forfeited his birthright due to an egregious sin (verse 4). The birthright was instead given to Joseph’s sons (1 Chronicles 5:1). All of Jacob’s sons received some sort of blessing.
While a birthright belonged to the firstborn son, anyone could receive a blessing. In the time of the patriarchs, such blessings acted as a “last will and testament” and were highly prized as a means of revealing God’s will.