I am a believer, but I think many many believers cannot accept your point on the inheritance of sin. The original sin belief has gone on for so many centuries, this teaching is so common in almost every modern church, that to teach otherwise might harm the effort of teaching Christ to the world.
I have read through your article and the questions and answers; it makes sense. But a believer would think Roman 6 talks about the old self who must be crucified or die, so the body of flesh must be sinful. Since everyone will die because everyone must have sinned when first born (you claim Adam's sin gave the world great impact), I John 3:4 is very plain and straight forward, but scripture claims no one can be declared righteous in obedience to the law. How do you balance Old and New Testament teaching?
"The entirety of Your word is truth, And every one of Your righteous judgments endures forever" (Psalm 119:160).
Truth is established by God's word, not the length of time a concept has been accepted or practiced. If time determined truth, then one could argue that idolatry should be acceptable because people have spent thousands of years worshiping idols. False teaching is what causes harm to the cause of Christ. The job of believers is to teach only as Christ would have us teach. "If anyone speaks, let him speak as the oracles of God. If anyone ministers, let him do it as with the ability which God supplies, that in all things God may be glorified through Jesus Christ, to whom belong the glory and the dominion forever and ever. Amen" (I Peter 4:11).
"What shall we say then? Shall we continue in sin that grace may abound? Certainly not! How shall we who died to sin live any longer in it? Or do you not know that as many of us as were baptized into Christ Jesus were baptized into His death? Therefore we were buried with Him through baptism into death, that just as Christ was raised from the dead by the glory of the Father, even so we also should walk in newness of life. For if we have been united together in the likeness of His death, certainly we also shall be in the likeness of His resurrection, knowing this, that our old man was crucified with Him, that the body of sin might be done away with, that we should no longer be slaves of sin. For he who has died has been freed from sin" (Romans 6:1-7).
It appears you are being loose with the symbolism in this passage. If the "body of sin" is referring to a physical body, then the physical body is done away with by being crucified with Christ. That would imply a physical death. But throughout this passage, the death mentioned is spiritual death to sin. Sin is being portrayed as a living organism that reigns over us but is put to death by the power of Jesus' death in the act of baptism. Much as Paul also said,
"that you put off, concerning your former conduct, the old man which grows corrupt according to the deceitful lusts" (Ephesians 4:22).
"Do not lie to one another, since you have put off the old man with his deeds, and have put on the new man who is renewed in knowledge according to the image of Him who created him" (Colossians 3:9-10).
You assume that these sins come upon a person at birth (or conception) but what verse states this? Sin is tied to life in this world, which is why God talks about the sins we commit in the flesh. "Do not love the world or the things in the world. If anyone loves the world, the love of the Father is not in him. For all that is in the world--the lust of the flesh, the lust of the eyes, and the pride of life--is not of the Father but is of the world. And the world is passing away, and the lust of it; but he who does the will of God abides forever" (I John 2:15-17).
Instead of stating we are sinners when firstborn, God charges that we are guilty, like Adam, because we also commit sin. "Therefore, just as through one man sin entered the world, and death through sin, and thus death spread to all men, because all sinned" (Romans 5:12). This then is the answer to your point about being saved by the law. We cannot be saved by law because we all break the law at some point in our lives, and we do so repeatedly.
"for all have sinned and fall short of the glory of God" (Romans 3:23).
"If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say that we have not sinned, we make Him a liar, and His word is not in us" (I John 1:8-10).
Notice in the last passage that we are told to confess our sins, not the sins of someone else who supposedly God then holds against us. We have sinned because we break God's law. "Whoever commits sin also commits lawlessness, and sin is lawlessness" (I John 3:4).
We do not live under the Old Covenant given to Moses, but that covenant was given to the Israelites by God. The nature of God, the nature of sin, and the nature of man have not changed. Thus, though the laws don't apply to us, we are still able to learn about God, sin, and man by examining the text.
"For whatever things were written before were written for our learning, that we through the patience and comfort of the Scriptures might have hope" (Romans 15:4).
"Now these things became our examples, to the intent that we should not lust after evil things as they also lusted" (I Corinthians 10:6).
"Now all these things happened to them as examples, and they were written for our admonition, upon whom the ends of the ages have come. Therefore let him who thinks he stands take heed lest he fall" (I Corinthians 10:11-12).
We can see many examples of using the Old Testament to prove and illustrate points throughout the New Testament. Start noticing how often the Old Testament is quoted by the New Testament and you will realize that the New Testament cannot be fully understood without a good understanding of the Old Testament.
"And therefore "it was accounted to him for righteousness." Now it was not written for his sake alone that it was imputed to him, but also for us. It shall be imputed to us who believe in Him who raised up Jesus our Lord from the dead" (Romans 4:22-24).
"For it is written in the law of Moses, "You shall not muzzle an ox while it treads out the grain." Is it oxen God is concerned about? Or does He say it altogether for our sakes? For our sakes, no doubt, this is written, that he who plows should plow in hope, and he who threshes in hope should be partaker of his hope" (I Corinthians 9:9-10).
You miss much of what God has told you when you don't consider the messages He left for His children in the Old Testament. Thus when Ezekiel explains that sin is not inherited, "The soul who sins shall die. The son shall not bear the guilt of the father, nor the father bear the guilt of the son. The righteousness of the righteous shall be upon himself, and the wickedness of the wicked shall be upon himself" (Ezekiel 18:20 and the verses that proceed this statement), has anything about the nature of sin changed between Ezekiel's day and our own? Was it possible that sin wasn't inherited back then, but it is now? If it wasn't inherited before then how did we get Adam's sin -- a man who lived in the Old Testament times? No, the nature of sin is consistent. Sin is the breaking of a law. Every person is individually guilty of breaking God's law because every person does so. It isn't because we can't help ourselves. If that was true then we could claim an excuse. No, it is far worse. We've all chosen to sin and thus can blame no one but ourselves for our predicament.