Summary: So what is to be the Christian's relationship to sin? Strictly speaking, he should not have such a relationship!
THE CHRISTIAN AND SIN
“Behold,” says John. Pause for thought and reflection. For it is indeed a wonderful demonstration of God's love that “we” should be called the sons of God (1 John 3:1).
This was not what we deserved, but as we know from other Scriptures, it was ‘while we were yet sinners’ that Christ died for us (Romans 5:8). This is addressed to Christians, of course: we who “were” sinners, but who are now ‘made righteous’ by the blood of Jesus (Romans 5:19). The prodigal son desired to be restored to his father as a servant (Luke 15:18-19), but when we come to God through the Lord Jesus Christ we are brought into all the privileges of son-ship.
Yet these privileges also carry responsibility (1 John 3:13).
Fathers and brothers have been known to bury an empty coffin in a gesture of rejection when a member of their family becomes a believer. Peer pressure is exerted against the new convert by former friends. Even employers use their economic advantage to try to extinguish the light of the new Christian.
The fact of the matter is that society feels threatened by the Christ within us. The world hates us because it hated Jesus first (John 15:18-19). The world “knows us not, because it knew Him not” (1 John 3:1).
Those who are beloved of Christ “are” the sons of God (1 John 3:2).
Upon self-examination we may not feel as if we are sons of God, but the Christian does not live by his feelings. It may not look to ourselves that we are any such thing, but the whole creation awaits the manifestation of the sons of God (Romans 8:19). What we are, and whose we are will not be fully evident until the Lord returns for His own.
Then we shall see Him as He is – not as he was, despised, rejected, mutilated and crucified, but as the risen conquering glorified Saviour. Then we shall be transformed, and fully conformed to His image.
Meantime, however, we are not to be idle. We have been made holy by Christ, but we are also to pursue holiness (1 John 3:3). The work of sanctification, which is God's work for sure, requires our participation (Philippians 2:12-13).
So what is to be the Christian's relationship to sin? Strictly speaking, he should not have such a relationship (1 John 3:4-5).
What is being spoken of here is the practise or habit of sin. Christ has borne away our sin in His death upon the Cross, so how shall we who are dead to sin live any longer therein? (Romans 6:2).
This is not to say that Christians do not fall into sin (1 John 1:8–2:2). However, such a falling out with God is also a falling out of our true character.
This is seen in the “whosoever” of 1 John 3:6. Everyone who abides in Him is of such a character that sin is alien to them. This is not speaking of an elite few, but of all Christians. For all the faults evident in the churches to whom Paul, for example, wrote, they were still addressed as saints in Christ Jesus. We are the sanctified ones, but it is still yet to appear what we shall be (1 John 3:2).
Conversely, a habit of sin betrays a lack of abiding familiarity with Jesus (1 John 3:6). There are times when our sins should lead us to examine whether we are really what we say we are, or whether we have been deceiving ourselves all along.
I like the familiar touch of John, who refers to his congregation as little children in danger of being led astray (1 John 3:7).
A tree is known by its fruit (Matthew 12:33). The apostle speaks first of the practise of righteousness, which proves our righteousness and our identification with the righteousness of Christ (1 John 3:7); then of the habitual sinfulness of the sinner, who is identified thereby with the devil (1 John 3:8). The devil's habit has been to sin from the very beginning, but the Son of God came to destroy the works of the devil.
John moves immediately from the eternal Son of God to the begotten-ness of Christians (1 John 3:9). If we are begotten of God we will not blatantly and habitually sin. His seed within us can only bring forth good fruit (Matthew 7:18). In fact, we are unable to continue in the practise of sin exactly because we have been begotten of God.
Ultimately our respective attitudes to sin and righteousness separate the saints from the sinners (1 John 3:10).
The chapter began with the love of God, which named us as the sons of God. One of the fruits of our son-ship, and of having the righteousness of Christ, is our love towards the brethren (1 John 3:10).