First John 3:4–10 strongly condemns sin, and leaves no excuse for it. While this warning is often interpreted as a ”litmus test” for salvation, John’s specific audience is actually Christian believers. Salvation is no excuse for sin, because all sin is from the Devil, not God. Sin always disrupts our ”walk” with God. And, those who only walk in sin and darkness cannot claim to be children of God.
For a more detailed summary select the link below.
“1 John 3:9” Bibleref.com
1 John 3:9
9 Whoever is born of God doesn’t commit sin, because his seed remains in him, and he can’t sin, because he is born of God.