3. Because they were the root of all mankind, the guilt of this sin was imputed to all their posterity descending from them by ordinary generation; and the same death in sin and the same corrupted nature was conveyed to their posterity.
4. All of our actual transgressions proceed from this original corruption, by which we are utterly unwilling, disabled, made opposite to all good, and wholly inclined to all evil. (WCF 6.3-4)
One of the great questions of the human experience is how did Adam’s sin actually have anything to do with us? How did his one mistake put us all at odds with our creator? How did our first parents rebellion become ours? Well this is what the confession answers here
First, “they (being Adam and Eve) were the root of ALL mankind.” Now what is meant by that? Well basically Adam was the head and the representative of all humanity who stood before the Lord (on our behalf) - he was “the root” and thus when he rebelled and sinned in the garden, it caused spiritual death (Gen 2:15-17, 3:17-19, Rom 5:12-21), which means his sentence cut him off from God and thus infests all who were to come from his union to his wife Eve (Gen 2:21-24). The confession puts it like this, “the guilt of this sin was imputed to all their posterity descending from them by ordinary generation”. To put it simply, because the wages of sin is death, that spiritual death not only killed Adam and Eve, but spread to all who was to come from them, and thus “the same death in sin and the same corrupted nature was conveyed to their posterity.” Pastor Voddie Bachum sums it up nicely, “we’re born as vipers in diapers” (see Gen 3:16, 4:1-7, Rom 5:12-21)
Think about it like this. Both my parents are British, they were both born in England and had lives there. However before I was born, they immigrated out to Australia and had me in the hills of Blackwood in the south of Australia. Now there was nothing that I could do to make them have me in the United Kingdom, they had already left that land and had me in the great Southland - a totally different country. And so very much like our first parents, they were in the kingdom of God, both physically and spiritually, but before any of us were born, they were cast out and we have all been born outside of that spiritual life - we are born as citizens of this world you might say and dead in trespasses (see Rom 3:9-12)
And thus second, because we are born spiritually dead and citizens of this world by nature - we naturally sin (Jn 8:44, Phil 3:20). 18th century theologian Jonathan Edwards hits the nail on the head, “we are not sinners because we sin, but we sin because we are sinners.” His point is simple and captured by the confession here, “All of our actual transgressions proceed from this original corruption.” So is it just that we are punished? Well, yes, because not only by nature are we sinners (something called original sin), but we sin continually and thus are guilty of personal sin as well.
All it takes is for any of us to reflect on God’s revelation and moral law, and we will quickly see (and hopefully agree) that “we are utterly unwilling, disabled, made opposite to all good, and wholly inclined to all evil.” That is why the redemption that is found in Christ Jesus is the answer to all of this. We were created by God and for God, we were created for relationship with him, but because of sin, we have been cut off and severed from true and eternal life. The good news is this, instead of leaving his people in this “country”, our God made away for us to be reconciled to him and to be bought back to that heavenly country. Jesus is the answer, Jesus is the perfect representative, the second Adam, He is the way the truth and the life and no one goes to the Father but by him (2 Cor 5:21, Jn 14:6, Rom 5:12-21).