Genesis 25:32
And Esau said, Behold, I am at the point to die: and what profit shall this birthright do to me?
Cross-reference
Malachi 3:14
Parallel
Malachi 3:14 uses nearly identical language: 'what profit' of serving God — same cynical calculus Esau applies to the birthright.
Deuteronomy 21:17
Contrast
Deuteronomy 21:17 codifies the firstborn's double portion as a legal right — the very inheritance Esau here casually dismisses as worthless.