Yes people who want to believe everyone sins, and quote that part of John’s letter to prove their belief and do so without feeling totally dishonest, I sure don’t understand.
(1 John 3:9-10) “No one who is a child of God sins because God's seed remains in him. Nor can he sin, because he is a child of God. This is what distinguishes the children of God from the children of the devil: whoever does not live uprightly and does not love his brother is not from God” New Jerusalem bible
They want people to believe John was telling those Children of God who can’t sin, that they can’t tell anyone, and if they do they will be lairs.
It takes a person who is very concerned about feeling themselves righteous even though they still sin, to believe that John was saying they were liars if they shared they no longer sinned?
I don’t believe people, when they quote 1 John 1:8-10 they expect any intelligent person to use that as to believe everyone still sins.
Also the way they are reading John’s Word, it only say if one tells someone they no longer sin they are lying. So they don’t know what John is truly saying at all.
You should know that the scripture you are quoting says: “If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness”
If one is forgiven of all unrighteousness are they not then sinless?
Could they then be liars if they say they are sinless?
By the way a Spiritual Christian only needs to confess his or her sins once. The Holy Spirit keeps a Christian free from sin.
(Romans 8:1-4) “The reason, therefore, why those who are in Christ Jesus are not condemned, is that the law of the spirit of life in Christ Jesus has set you free from the law of sin and death. God has done what the Law, because of our unspiritual nature, was unable to do. God dealt with sin by sending his own Son in a body as physical as any sinful body, and in that body God condemned sin he did this in order the Law’s just demands might be satisfied in us, who behave not as our unspiritual nature but as the spirit dictates.”