Biblical birthright seller (4)
I believe the answer is:
esau
'biblical birthright seller' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for esau that I've seen before include "Hairy biblical man" , "Son of Isaac and Rebecca" , "Birthright seller (Bible)" , "Rebecca's son" , "Twin brother of Jacob" .)