How do we know the Adamic sin nature is inherited since Adam?

Paul’s epistles reveal the true nature of the old Adam and provide the understanding that the Adamic sin nature is inherited ever since Adam. While the Old Testament calls the heart desperately wicked and Jesus taught the heart was wicked, only Paul’s writing makes this inherited sin nature clear.

Les explains that when you return to I Corinthians 15, you see why Paul is the one who reveals many things the rest of Scripture does not even touch on. He says it is in Paul alone that we find the true nature of the old Adam. Although the Old Testament says the heart is desperately wicked and Jesus taught that the heart was wicked, Les teaches that it is not until Paul’s writing that you get the understanding that this Adamic sin nature is inherited ever since Adam.

Where does the Bible teach that the sin nature is inherited from Adam?

The Bible teaches that the sin nature is inherited from Adam through the Apostle Paul's epistles, where he alone reveals the true nature of the old Adam. This understanding is not found until Paul's writing, particularly as he explains it in passages like I Corinthians 15.