I will answer this one, but note, I am not about to enter debate with you as 1) I do not wish to argue 2) I am unwell atm.
Some use this verse – if we say we have no sin we deceive ourselves 1 John 8, to justify their position but they are taking it out of context as John 1 was written to counteract heresy. The Latin version says “Epistle to the Pathians” adopted by Ancient Fathers, defended by Grotius, not in Greek. Whoton conjectures on the Greek superscription (to virgins) because the letter was addressed to 'uncorrupted Christians' therefore holy ones. John was warning those who were in danger of hearing Zorostrian principles and therefore Gnosticism which taught that man could be righteous in spirit and still sin in the flesh, which is nowadays recognised as imputed righteousness which has been refuted by holiness preacher George Fox of the early Quakers.
The basis of this error that a man can sin and still be in Christ, was made popular and was spread through the church by Augustine, when he changed his doctrine in dispute with Pelagius and the early Christians, to an unheard of rendition that made Romans 7 to be the normal experience of a believer. 1 John 1:6,7 say that if we say we have fellowship with Him ans 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 with one another and the blood of Jesus cleanses us from ALL sin. He continues, If we say 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 our sins and to cleanse us from ALL unrighteousness. 8,9.
We can see that John is comparing walking in the light to walking in darkness that is to say walking in the flesh compared to walking in the Spirit. He is describing two opposing states which corresponds perfectly with the teaching of the Apostle Paul when he talks about carnal or fleshy believers against those walking in the Spirit or Spirit filled.
The benefits of walking in the Spirit are:
1)we have fellowship with one another
2)by confessing our sin we are forgiven
3)we will then be cleansed by the blood of Jesus from all unrighteousness.
However if we walk in the flesh and sin we are deceived and are blind to our need to come to Christ for His cleansing from ALL sin as are those today who are misled by Gnosticism by preachers of positional righteousness. John corrects that fallacy by saying Little children let no man deceive you, he that doeth righteousness is righteous even as He is righteous 3:7. This is the test, we must not be in just a position of righteousness and depend on coming to Christ in the past for forgiveness, but must be in the present reality, must be like Christ and walking in perfect obedience through the power of the Holy Spirit.
But whoso keepeth His word, in Him verily is the love of God perfected 2:5
My little children, these things I write unto you that ye sin not 2:1
Whosoever is born of God doth not commit sin 3:9.
The problem with your argument is that you are bringing in Gnosticism, Augustine, Pelagius, George Fox, and church history when John himself tells us what he means. I am going to stay with Scripture.
John does not say, “If the Gnostics say they have no sin.” He includes himself and his Christian readers:
“If we say that we have no sin, we deceive ourselves, and the truth is not in us” (1 John 1:8).
Notice what immediately follows:
“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).
Then John says again:
“If we say that we have not sinned, we make him a liar, and his word is not in us” (1 John 1:10).
John says “we” throughout the passage. He then addresses believers directly:
“My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous” (1 John 2:1).
That directly contradicts your interpretation. John commands Christians not to sin, but he also recognizes that a Christian may sin and tells believers that when this happens, “we have an advocate with the Father.”
First John 3:9 does not contradict 1 John 1:8 or 2:1. In context, John is describing the character and continuing conduct of someone born of God. The ESV renders the point clearly: “No one born of God makes a practice of sinning.” John is condemning a life characterized by sin. He is not teaching that a Christian reaches a condition in which he can truthfully say, “I have no sin.”
First John 1:8 does not excuse sin, and I have never used it that way. Christians are commanded to pursue holiness and put sin to death. But Scripture does not permit us to turn that command into a claim of personal sinlessness.
There is a difference between not practicing sin and claiming to be without sin. John commands the first and warns against claiming the second.