Historicity of Adam
"I want to close with a lingering Christological worry. Scientific plausibility is the key; can we still believe doctrines that are implausible by the lights of current science? We can invert the question: If scientific plausibility should guide the expectations we bring to Scripture, then why would we be Christians? Why would we believe that the Son of God became a man? That he died and rose again after three days? That he ascended into heaven? These fundamental Christian beliefs contradict everything we know from mainstream science. If we can no longer believe Adam was historical, then why should we believe in the resurrection? In The Evolution of Adam, Peter Enns answers this way: “For Paul, the resurrection of Christ is the central and climactic present-day event in the Jewish drama—and of the world. One could say that Paul was wrong, deluded, stupid, creative, whatever; nevertheless, the resurrection is something that Paul believed to have happened in his time, not primordial time.” That misses the point. We’re told that we can’t affirm a historical Adam because it’s scientifically unbelievable, but why trust Paul on the resurrection when that, too, is scientifically unbelievable? Or, to flip the script, if we believe the resurrection, then a historical Adam is no biggie." - Hans Madueme
Jesus physical death was what paid for the sin that led to (among other things) Adam's physical death (the very sin which first brought death into the world). For if Jesus' physical death was not payment for what led to Adam's physical death (and all death on the planet) then there is no gospel. Remember, Jesus' death frees both men and creation (Rom 8.20-21) from corruption and death. For as the king goes, so goes the nation. Therefore those who embrace theistic evolution are embracing an untenable position which is contrary to the gospel itself. Further, to believe the "last enemy" was part of God's original creation is to profoundly misrepresent the heart of the Scripture. It imputes to God that which is only imputable to man - sin and death. And so followed to its logical conclusion, the theistic evolutionist would have Jesus dying for something God did, not for something man did - a complete perversion of the truth.
Christianity is a historic religion, not a philosophy of life, and it is based on certain events that took place in real history. A historic Adam is essential to that history and those who deny this have sold the farm and no longer have anything which resembles biblical Christianity.