From the post The Bible’s Most Overlooked But Really, Really Important Guy « Cognitive Discopants
Jesus was the answer for fallen Israel, not fallen Adam.
This is the true metanarrative of the Bible. In fact, some have suggested (persuasively, I think) that the story of Eden/the Fall/the expulsion from Paradise is itself a metaphor for the overarching narrative of Promised Land/unfaithful Israel/exile. The gospel story is the story of God’s redemptive plan for a nation that had lost its way – a nation into which God would ultimately graft all of humanity.
If modern genetics casts doubt on the historicity of Adam (and it does), rather than undermine the gospel, this realization may actually help the church to recover the authentic gospel, properly conceived (as Scot McKnight has recently put it), “as the completion of the Story of Israel in the saving Story of Jesus.”