Q&A: Matthew and Luke give very different genealogies for Jesus in their Gospel accounts. I've heard you say that Matthew is recording Joseph's lineage while Luke is recording Mary's. What proof do we have that this is correct?
While I personally believe that Luke is giving our Lord's maternal genealogy through Mary, my position is based on clues rather than proof. And yet, I believe those clues are compelling.
The key is that Matthew and Luke each give a different name for the father of Joseph. Matthew says Joseph’s father was Jacob (Matthew 1:16), while Luke says it was Heli (Luke 3:23). Since the Jews were extremely careful when recording genealogies, it seems highly unlikely that these two men just got it wrong, especially since they were dealing with a name that was only one generation removed. So, how do we explain this?
My belief is that since there was no specific Koine Greek word for “son-in-law,” Joseph was called the “son of Heli” by marriage to Mary — which means Mary was Heli’s daughter. Also, Luke speaks of Jesus being the son of Joseph, “as was supposed” (Luke 3:23).
The other clue that leads us to believe that Luke is recording Mary's genealogy is the fact that no other Gospel writer gives more information about Jesus' life as a child. It seems very likely that Luke spent time with Mary getting details that could have come from no other source.
The benefit of recording both Mary’s and Joseph’s family lineage is that Jesus is seen as the legitimate son of David whether determined by law through Joseph (as recorded by Matthew) or by blood through Mary (as seen in Luke). Some people object to this conclusion based on the fact that tracing someone's genealogy through a woman was extremely rare. I agree...but a virgin birth is even more rare!