Original sin is rooted in humanism, not not the Bible...
Please give me a chance to explain from scriptures but first with a short look at the doctrine’s history.
Original sin is a belief that Augustine brought into so-called Christiandom. Before him it was not taught in the church or scriptures.
Calvin further popularized the idea and it has been embraced in modern day Christianity despite being unsupported by the Bible and the earliest church teachings. Adam's sin brought death into the world but just as Adam sinned, we all choose to sin or not to sin. We all die for our own sins. We cannot blame Adam like Adam tried to blame Eve. But every one shall die for his own iniquity: every man that eateth the sour grape, his teeth shall be set on edge. Jeremiah 31:30 I prefer to carry a biblical mindset instead one rooted in humanism or even further back, in gnostic heresy. In all reality, humanists have been around since around the beginning of time, even before the gnostics. Many people for many years have believed that the end of all being is the happiness of man and that God was one of many of those means to achieve that end. This is what humanism essentially is. Humanism provides a mindset of inevitable sin via the proverbial excuse, "I am destined to mess up..." or sin, if you will..."after all, I am only human". The humanist as well as today's Christian Church teaches this, for the most part. The Bible teaches that with God all things are possible (Matthew 19:26, Mark 10:27) and that all things are possible to him that believeth (Mark 9:23) and that I can do all things through Christ which strengtheneth me. (Philippians 4:13). Today's christian doctrines have reworded or corrected these scriptures by submitting to humanism. We are now told in essence that we cannot do all things through God the Father and His Son Jesus Christ because we are, after all, "only human". We are not just humans but we are more than conquerors through God! We are victorious through Jesus' victory over death! Nay, in all these things we are more than conquerors through him that loved us. Romans 8:37 But thanks be to God, which giveth us the victory through our Lord Jesus Christ. 1 Corinthians 15:57 But Jesus beheld them , and said unto them, With men this is impossible; but with God all things are possible. Matthew 19:26 And Jesus looking upon them saith, With men it is impossible, but not with God: for with God all things are possible. Mark 10:27 Jesus said unto him, If thou canst believe, all things are possible to him that believeth. Mark 9:23 I can do all things through Christ which strengtheneth me. Philippians 4:13 So don't wake up this morning thinking you are destined to sin but instead greet the day knowing that with God you can live without sin but remember always that if you do fall He is there quickly to forgive... If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness. 1 John 1:9 By referring to this verse I can imagine many will say, "verse 8 says we all have sinned!" and they will try to claim victory in the debate, alongside their humanist friends. One cannot get the full context of 1 John 1:8 and 10 without utilizing verses 6, 7 and 9. If we say that we have fellowship with him, and walk in darkness, we lie, and do not the truth:  But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.  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. 1 John 1:6-10 Verse 8 speaks in context about the man who walks in darkness as mentioned in verse 6. Verses 7 and 9 speak to the other man, the one who walks in the light. Verse 7 says "the blood of Jesus Christ his Son cleanseth us from all sin". You cannot say you have been cleansed from all sin and say that you still have sin. This violates the universal law of non-contradiction. Please feel free to look that up if you don't know what that means. If you choose to sin and to not repent (willfully and actively living in sin) and still claim to have fellowship with God then you are that person referenced in verses 6 and 8. You are a humanist more so than a Christian as per God's Word.
In conclusion, the humanist will look to ascribe blame for his sin elsewhere while the Christian fully acknowledges that it is his sin and no one else's and that he deserves God's wrath for every bit of it. A humanist will diminish sin and excuse it one way or another and walk in darkness as the result but the Christian will acknowledge that he is a reprobate sinner and will repent of sin so that he can walk in the light with the Lord.
The idea of original sin is really just another excuse for sin when you unravel the idea down to it's core.