How does these scriptures harmonize.

1 John 3:8-9
King James Version


8 He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.

9 Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God.
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1 John 2:3-4
King James Version

3 And hereby we do know that we know him, if we keep his commandments.

4 He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.
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Does a born again Christian sin?

Sounds like the rich young ruler.🤭

A Christian can sin. The difference between a sinner (unsaved person) sinning and a Christian sinning is that the Christian is not a "slave" to sin, for he has received the saving grace of God.

A sinner does not know the saving grace of God and lives in his sin and, if he does not repent, will die in his sin. The Christian has the precious blood of Jesus to cleanse him of sin. Now, folks will argue this, but, IMO, when a Christian sins, he must ask for forgiveness for that sin to receive forgiveness for the sin. I say this because Jesus taught us that when we pray we should pray "and forgive us our trespasses as we forgive those who trespass against us."

Christians are not yet the "perfection" they will one day be. The Apostles show us this in the way they lived their lives. They were not perfect, but they were saved and washed in the blood.

the question id formed by two extremes

1. legalism
2. carnality


Jesus said whosoever calls on the name of the Lord will be saved, Yet you still must obey the Lord. That being said when CHRISTIAN AS pETER WHO WAS ADMONISHED by Jesus about the gentiles Did Jesus say to Peter YOU are not my child or I do not know you?

No. Jesus was patient with Peter and I might add Jesu had already ascended.

The issue is not the issue. The devil has confused many professional Christians about the mercy and patience OF GOD.

lEGAISM has you not good enough. Carnality has you unwilling to give up those things that hold you back.

BUT HERE is the issue Satan hates you because YOU can be forgiven And HE never will. And it drives him nuts. Because he is self-righteous and hates that you have what God will not give him. As long as you have breath you are in the process of being shaped and made into the very image of the divine Son.
God will hold you accountable and be long-suffering. He will correct you yet be patient. He will forgive you and still want you to be obedient.
many want to make God unreasonable it is the oldest trick satan can use he used it on Eve, and he is using it on many people.

I think it's more like the blood of Jesus Christ's sacrifice pefects us and God remembers our sins no more. Meaning we won't be judged according to our sins:

Hebrews 10:14-17
14For by one offering he hath perfected for ever them that are sanctified. 15Whereof the Holy Ghost also is a witness to us: for after that he had said before,
16This is the covenant that I will make with them after those days, saith the Lord, I will put my laws into their hearts, and in their minds will I write them;
17And their sins and iniquities will I remember no more.

The reason we confess our sins to receive forgiveness is because sin grieves God, but it does not unseal us from the Holy Spirit:

Ephesians 4:30
30And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption.

The kind of forgiveness confession brings is a restored relationship. Think of the prodigal son who, despite his many woes, was still a son.

Luke 15:21-24
21And the son said unto him, Father, I have sinned against heaven, and in thy sight, and am no more worthy to be called thy son. 22But the father said to his servants, Bring forth the best robe, and put it on him; and put a ring on his hand, and shoes on his feet: 23And bring hither the fatted calf, and kill it; and let us eat, and be merry: 24For this my son was dead, and is alive again; he was lost, and is found. And they began to be merry.

In 1 John, he is speaking f a lifestyle of sin, he who sins continuously or habitually. Has never seen God, he who has been born of God can not sin continuously or habitually. Ie a lifestyle of sin.

The part of the Christian that is born again is the spirit. This is where the Lord Jesus lives in the person of His Holy Spirit. Our spirit man does not sin.

I've never met a born again believer who loves to sin. The new spirit is alive to God and sensitive to God's holy and righteous nature and character. We no longer produce sin. We are still able to sin, because we still have temptation from the self of the soul and from Satan. As we depend more and more on Lord Jesus, two things happen. First, we hate sin more and more. Second, we start to see sin more clearly. God's intent is to bless us by setting us free from bondage to sin. Many Christians are obsessed with sin as if it is not already forgiven. God expects us to sin. He has made provision for cleansing through the blood of Christ. However, we should find that sin becomes the exception, as we grow in the knowledge of the truth.

Once the New covenant begins with the nation of Israel, all of them are born of God, and will have the law written in their hearts.

So during the millennial reign of Christ during those 1000 years, they cannot sin, they become impeccable to sin.

The Body of Christ will also be impeccable to sin after we get our redeemed bodies.

This may sound pedantic, but it is important. Christians are already forgiven (Ephesians 1:7). What Christians must do is confess their sin (1 John 1:9). Sin should not overly dominate our thinking. We can become as if spiritually paralysed, afraid to do anything in case we make a mistake. We need to know who we are in Christ and live in the light of that.

We do need to forgive those who have offended us. That's a separate issue that I'm happy to discuss if you wish.

I read your post again and I’m not sure I agree with the Christian Must ask for forgiveness more than the first time they come to JESUS unless you mean asking for forgiveness Is the same as renewing our minds.

Many see that scripture to mean we have to confess every sin after we have already gotten saved to be forgiven.

1 John 1:9
King James Version

9If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness

This is when we hear " But a really authentic, legitimate, real , true Christian doesn't practice , habitually, continues, unrepentant , not feels really sorry / feels bad over his sin , goes on sinning, eventually returns, endures , perseveres, ect ect .
Aka ' Lordship salvation ' .

///Jesus taught us that when we pray we should pray "and forgive us our trespasses as we forgive those who trespass against us."////
Jesus taught THEM . And this is before Jesus died for the sins of the world .