1 John 3:9 does not stand alone, separate from the rest of God's word, nor above it. Rather, the verse is qualified and clarified by
all that Scripture has to say about the believer and sin. And because this is so, it's impossible to understand John in the way you're trying to here,
justbyfaith.
See:
1 Corinthians 3, 5, 6, 11:17-34, Galatians 3:1-3, 4:9-12, 1 John 1:7-10, Romans 7:15-25, Revelation 2-3, etc.
As better translations of Scripture have been made, the sense of John's words in
1 John 3:9 has been more clearly rendered and come into fuller accord with the rest of God's word.
1 John 3:8-10 (ESV)
8 Whoever makes a practice of sinning is of the devil, for the devil has been sinning from the beginning. The reason the Son of God appeared was to destroy the works of the devil.
9 No one born of God makes a practice of sinning, for God’s seed abides in him, and he cannot keep on sinning because he has been born of God.
10 By this it is evident who are the children of God, and who are the children of the devil: whoever does not practice righteousness is not of God...
John never indicated that the believer will be totally sin-free at some point, only that the genuine believer will not "make a practice of sinning"; that is, the believer will not persist in sin without pang of conscience, or conviction of the Holy Spirit (
John 16:8; Revelation 2-3), without the discipline of the God occurring (
Hebrews 12:5-11), without ever looking up from the pigpen and thinking, "I will go to my Father and say I have sinned against heaven and before you" (
Luke 15:18). Though believers inevitably sin, they distinguish themselves as genuine believers by desiring God (loving Him) more than their sin and so act to overcome their sin by the means God has laid out in His word (repentance, confession, submission, faith). But every person who comes to God has layers of sin in their life, most well-hidden from the person's view, that not even a lifetime of walking with Him is necessarily sufficient to uncover and remove. These are sins of attitude, and motive, and desire, buried deep, complicated and subtle, such that, without God's help, they cannot ever be seen for what they are by the born-again person. That these sorts of sin are instantly eradicated at conversion is obviously nonsense for they are, in their subtlety, complexity and depth, often thought to be good and right things and celebrated by the one claiming to be free of all sin.
Then, too, the idea that sinless perfection is possible for a believer is, on its face, a silly idea because "perfection" is an indescribable condition, unknown in its actual dimensions to human beings. We refer to God as "perfect," but we don't fully understand what we're saying, what it is to be
truly without flaw, to be in a condition that is so complete and excellent, so absent of any flaw, or lack, or deviation that it cannot be improved or diminished in the slightest way. And so, the Christian man who tries to assert that he is sinlessly-perfect I understand immediately to be fooling himself, claiming to be what he cannot actually understand, unable to hit the target of perfection he claims that he does because he has no proper, precise, and clear idea what it is.
And then, there are the many questions that arise against the notion of sinless perfection:
Why does God need to discipline His children (
Hebrews 12:5-11) if they are
perfect in their obedience to His commands, and so, without sin?
Why does the Spirit convict the 7
churches of Asia minor, if they are incapable of sin (
Revelation 2-3)?
How is Paul's description of the divisive, contentious, sexually-immoral believers at Corinth as "carnal babes in Christ," "brethren," "temples of God," those who "are Christ's," and so on, possible, if, as such, they were unable to be carnal and sinful? (
1 Corinthians 3, 5, 6, 11;17-34)
What of
1 John 1:8-10 where John explicitly says that anyone who claims to be without sin is self-deceived and a liar?
Why is every letter of the New Testament filled with instructions, commands and prohibitions
to Christians if they are, as a natural consequence of being saved, unable any more to sin?
And so on.