1 John 1:8 says, "If we claim to be without sin, we deceive ourselves and the truth is not in us."
However, 1 John 3:9 says, "No one who is born of God will continue to sin, because God's seed remains in him; he cannot go on sinning, because he has been born of God."
At first glance, this appears to present a glaring contradiction. Do Christians sin, or not? In one verse, John tells his Christian audience that we all sin. Then, in the very same letter, he says that if we're really Christians, we can't continue to sin.
I've heard many inadequate explanations for this passage. The best of these weak arguments says that the key to the interpretation is the tense of the verb used in 1 John 3:9. It says we can't "continue" to sin. In other words, this argument continues, when we sin and confess it, we won't be repeating that same sin again regularly. However, this proves of little comfort to many Christians who find they're confessing some of the same sins almost every day. In fact, this argument seems to serve only to make some true believers question their salvation.
2 Corinthians 5:17
To unravel this dilemma, we must start with 2 Corinthians 5:17: "Therefore, if anyone is in Christ, he is a new creation; the old has gone, the new has come!"
Newness of Life
This is a profound verse which is often quoted but rarely thoroughly understood. It's not just saying that when I became a Christian, I underwent a great change. It's actually saying that I went away (died, Romans 6:4-11) and was replaced by a brand new creation. Romans 5:14-15 explains that when we are born physically, we are born into lives of flesh and sin, and we have Adam as our federal headship. Then when we are spiritually born again, we are born into a life in the spirit with Jesus as our federal headship. Romans 7:6 calls this the newness of the spirit. This in not unlike what happened to Saul when he was being chosen as Israel's first king. In 1 Samuel 10:6,9, when the Spirit came upon Saul, "he changed into a different person." God changed his heart. The only difference for us is that while the Spirit eventually left Saul in 1 Samuel 16:14, we Christians are indwelt with the Spirit forever. We are new creatures in Christ (2 Corinthians 5:17), and what God sees when He looks at us is that new creation in His Son, rather than our old self.
Romans 7:15 - 8:1
Even Paul struggled with sin in his everyday life. In Romans 7:15, he says, "I do not understand what I do. For what I want to do I do not do, but what I hate I do." Verse 18 goes on to say, "I know that nothing good lives in me, that is, in my flesh. For I have the desire to do what is good, but I cannot carry it out." Here is our first clue to the puzzle. Obviously, Paul was a Christian, and he sinned as a Christian. In fact, verse 19 says, "For what I do is not the good I want to do; no, the evil I do not want to do-- this I keep on doing." Not only did Paul sin, but he kept on sinning. He continued to sin, which 1 John 3:9 says that Christians can't do.
However, verse 17 says, "As it is, it is no longer I myself who do it, but it is sin living in me." Although this sounds like an excuse, it's a reality. Verse 20 says, "Now if I do what I do not want to do, it is no longer I who do it, but it is sin living in me that does it."
In other words, when Paul was an unbeliever, and God looked at Paul, He saw Paul's soul. Paul was constituted by his soul. He was just a soul, and his body was only a tent (2 Corinthians 5:1-4). However, once Paul became a new creation (2 Corinthians 5:17) in Jesus Christ, when God looked at him, He saw Paul's new spirit. Paul was no longer constituted by his soul. Now "Paul" was a spirit. Unfortunately, in his earthly life, he continued to drag along his old soul and body (the flesh). Romans 7:21 says, "So I find this law at work: When I want to do good, evil is right there with me." Although the spirit has power over the flesh, this flesh can still sin. Furthermore, Romans 7:22-23 says, "For in my inner being I delight in God's law; but I see another law at work in the members of my body, waging war against the law of my mind and making me a prisoner of the law of sin at work within my members." Paul's spirit wants to do good, but he sees his body sin.
Romans 7:24 says, "What a wretched man I am! Who will rescue me from this body of death?" So what's the answer? The answer is found in Romans 7:25 and 8:1, "Thanks be to God--through Jesus Christ our Lord! So then, I myself in my mind am a slave to God's law, but in the flesh a slave to the law of sin. Therefore, there is now no condemnation for those who are in Christ Jesus." Remember, Paul is his spirit (and mentality), which is a slave to God's law, although his flesh (but not he, himself) is a slave to the law of sin. Therefore, since Paul is his spirit, and he is no longer his flesh,
he is not charged with any sin his old flesh might do. He is not condemned, because,
in the eyes of God, he is perfect, in Christ Jesus.
1 John 1:8 is true, because the flesh associated with each Christian still sins. However, 1 John 3:9 is also true because the new Christian cannot sin. It's only the flesh associated with him that's sinning. In Romans 7, when Paul says he sinned, he's referring to the flesh associated with him, as in 1 John 1:8. On the other hand, passages such as 1 John 3:9 are referring to the Christian himself; i.e., his spirit.
So, is it OK to continue to sin? Paul anticipated this question in Romans 6:1, "What shall we say, then? Shall we go on sinning so that grace may increase?" Then, of course, he gives us the answer in verses 2 and 12, "By no means! We died to sin; how can we live in it any longer? . . . Therefore do not let sin reign in your mortal body so that you obey its evil desires." Since the spirit has power over sin, we are still responsible for ensuring that the flesh doesn't sin. Those sins are still our responsibility in this life and they still harm us and others, but we will suffer no condemnation for them from God now or in eternity.
God sees me (my essence) as "me, in the Spirit," and not "me, in the flesh." In other words, even though "I" keep sinning, it's not really me--it's the sin living in me (my flesh, which coexists with "me, in the Spirit").
Romans 8:23-25, "... we ourselves, who have the first fruits of the Spirit, groan inwardly as we wait eagerly for our adoption to sonship, the redemption of our bodies. For in this hope we were saved. But hope that is seen is no hope at all. Who hopes for what they already have? But if we hope for what we do not yet have, we wait for it patiently." Although we have the Spirit, we await the redemption of our bodies (flesh--which we also still have), but we do not yet have (physical) freedom from our corrupted flesh. Also, this brings into light the very definitions of these words: the relationship of our bodies to our flesh. Our bodies are our literal flesh.
From Do Christians Sin (1 John 1:8 vs. 1 John 3:9)? by Owen Weber