Question: "Why is the birthright so emphasized in the Bible?"
Answer: The birthright is emphasized in the Bible because it honored the rights or privileges of the family’s firstborn son. After the father died, or in the father’s absence, the firstborn son assumed the father’s authority and responsibilities. However, the Bible also shows that the father could rescind the birthright and pass it on to a younger son. A good example of this is the case of Jacob and his twelve sons. Reuben was the eldest, but the birthright was given to Joseph’s sons. Even then, Jacob blessed the younger son, Ephraim, above the elder, Manasseh (Genesis 37:19-22; Genesis 49:1-4; Genesis 49:22-26).
In addition to assuming the leadership role in the family, the recipient of the birthright inherited twice that received by the other sons. In cases where a husband might have more than one wife, the birthright always went to the firstborn son of the father and could not be awarded to the son of a favorite wife without proper justification (Deuteronomy 21:15-17) or if the firstborn son’s mother was a concubine or a slave (Genesis 21:9-13; Judges 11:1-2).
The birthright of a king’s firstborn son included his succession to the throne (2 Chronicles 21:1-3). King Rehoboam of Judah violated this tradition by passing the birthright to Abijah, his favorite son. However, to avoid trouble with the older sons, the king paid them off (2 Chronicles 11:18-23).
As New Testament Christians, we have an inherited “birthright” status through Jesus Christ as the firstborn Son of God (Romans 8:29; Colossians 1:15; Revelation 1:5). As God’s only begotten Son, Jesus received the kingdom from His Father and is Lord of all (Acts 2:36; Philippians 2:9-11; Revelation 19:16). Christ promises to share with us His kingdom and inheritance (Romans 4:13; Galatians 3:29; Ephesians 1:18; Hebrews 11:16).
Christians are warned not to imitate Esau who, on impulse, gave away his birthright for a bowl of stew (Hebrews 12:16-17; Genesis 25:19-34). Because of his foolishness, Esau lost his birthright and the blessings of his father (Genesis 27). The lesson for us is to respect what is holy. We should never throw away what is important, godly, or honorable for the sake of temporary pleasure.
Our focus is to remain on Jesus, the appointed heir of all things (Hebrews 1:2; Psalm 2:7-8; Matthew 28:18). And we, through His grace and our faith in Him, are counted as joint heirs (Romans 8:17; Galatians 3:29; Titus 3:7).