All "original sin" refers to is the inherited corruption of human nature, a consequence of Adam's sin which all of humanity, being ultimately descended from Adam, has inherited from him
All anyone needs do is examine their own selves to readily see where we've inherited that sinful nature - be it in our greed, lust, hatred and anger, envy, pride, sensuality, jealousy, drunkenness, etc. (Gal 5:19). We are demonstrably imperfect beings.
The bible affirms it as well in numerous places: PS 51:5 ("
Behold, I was brought forth in iniquity, and in sin my mother conceived me."), Gen 8:21 ("
the intent of man’s heart is evil from his youth..."), Eph 2:1 ("
And you were dead in your trespasses and sins, in which you formerly walked according to the course of this world...").
Question is - when is this sin of ours imputed to us? When are we actually deemed guilty of it? The instant we exited the womb? Some define this as "original sin" - believing the instant we exit the womb we're damned to hell, merely because we have inherited Adam's sinful nature (which we have), yet BEFORE we've ever actually committed any sins. I don't believe the bible teaches this - I mean, what sins can a newborn commit that rightfully eternally condemns him? It's a fair question.
Back to Genesis 8:21 - what defines "youth?" Isaiah made this statement about the child Immanuel (Jesus):
"He will eat curds and honey at the time He knows enough to refuse evil and choose good. For before the boy will know enough to refuse evil and choose good, the land whose two kings you dread will be forsaken." (Isa 7:15f)
While there is no explicit age defined here, clearly the concept is articulated - that at some point we reach an age where we will know there is a difference between right and wrong and what that difference is. Moreover, at some point after this, because of our inherited adamic nature, we will make the choice to knowingly do wrong; and it's at this point we're held accountable for our sin. But there's nothing in the bible that stipulates at what age this occurs, so it's pointless to be dogmatic about it.
David, after committing adultery with Bathsheba, fasted and wept for the child she bore by him, praying he wouldn't die. But when he did die, David quit praying and fasting and was challenged as to why. He simply stated:
“While the child was still alive, I fasted and wept; for I said, ‘Who knows, the Lord may be gracious to me, that the child may live.’ But now he has died; why should I fast? Can I bring him back again? I will go to him, but he will not return to me.” (2 Sam 12:22f)
The child had done nothing wrong, but died anyway, and David, knowing the child's death was a consequence of his sin, not the child's, was nevertheless convinced he would go [to heaven] to the child.
Again, there's no solid warrant for being dogmatic about this, but I believe the bible DOES acknowledge grace to those [newborns and beyond] who have yet to reach that age where they know the difference between right and wrong, and grants them according to His grace forgiveness for when they ignorantly do wrong.
Faith/belief is fundamentally the readiness to obey, to obey on the basis of knowing who God is and who we are in relation to Him. We aren't mature enough to know this having just exited the womb; and it takes time for a child to mature to the point they know the distinction and can make an informed decision to obey or not to obey. I firmly believe God's forgiveness covers us until we reach that point in time. After that, we need to seek Him of our own accord for His forgiveness, being willing to confess our sins, acknowledge His sacrifice on the cross for us, and obey Him. (Heb 3:16-19)
