Acts 2:38 is the fulfilling of Zec 12:10 "And I will pour upon the house of David, and upon the inhabitants of Jerusalem, the spirit of grace and of supplications: and they shall look upon me whom they have pierced, and they shall mourn for him, as one mourneth for his only son, and shall be in bitterness for him, as one that is in bitterness for his firstborn."
Regarding 1 Cor 2:14 I suggest we are all born "natural men." Whether we choose Christ or not is our personal decision.
Paul, speaking about his vision on the Damascus Road tells how Jesus said, "I have appeared to you for this purpose, to appoint you as a servant and witness to the things in which you have seen me and to those in which I will appear to you, delivering you from your people and from the Gentiles—to whom I am sending you to open their eyes, so that they may turn from darkness to light and from the power of Satan to God, that they may receive forgiveness of sins and a place among those who are sanctified by faith in me."
(Act 26:16-18 ESV)
So you see, even the most wicked hearts in the grip of Satan can be changed.