The Word of God teaches that we need self-knowledge – self-knowledge of the most important kind, namely, knowledge of our sin and misery. This does not mean that we attain this knowledge ourselves; in fact, only from the Word of God do we learn that we are sinners. Apart from God’s revelation, we would not know our true natural condition (conceived and born in sin and inclined to all manner of evil), nor our true natural status (guilty and condemnable in the sight of God). Throughout our whole life we will have to deal with the reality of sin. Just before the text, John writes,

If we claim to be without sin, we deceive ourselves and the truth is not in us.John 1:8

Sometimes believers worry whether all their sins are really forgiven. Particularly a sin against which we must struggle time and again but do not seem to make much headway in overcoming, can make us wonder whether the LORD will really forgive us.

But then we may focus on the words of the text: “If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.” John speaks about confessing our sins without going into details about what confession means. You will understand that this is an honest confession made with integrity, which means that we have broken and contrite hearts and are heartily sorry for our sins and fight against them. God is not just interested in words, but in the attitude of the heart. John says that if we confess our sins, God is faithful and just and will forgive us our sins.

Notice carefully that John does not just say that if we confess our sins, God will forgive us our sins. John says, “If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.” There is a guarantee for the forgiveness of our sins, and it lies in God’s faithfulness and justice!

God is faithful – faithful to his promise of forgiveness! Scripture records in many places the promise of forgiveness; that promise even lies at the heart of the covenant. And we know from Scripture that God is faithful to his covenant promises. His words are spoken in truth, and stand forever! God faithfully keeps his promise of forgiveness because He is the faithful One!

God is also just – just in the sense that He does what is right and good. This is closely connected with God’s faithfulness because if God says He will do something, it is a matter of his justice that He will then also do it. God sent his Son into this world to pay the price for our sins, and since the price has been paid, God, in his justice, will not exact the price from us. Christ bore the wrath of God against our sins so that we may be filled with God’s blessing. Therefore, it is a matter of God’s justice to grant us the blessing of forgiveness when we confess our sins.

Yes, in his faithfulness and justice, God will forgive us our sins and purify us from all unrighteousness. Therefore, the guarantee of our forgiveness lies in the very fact of who God is! He is the faithful and just One!

Forgiveness means that “...as far as the east is from the west, so far has he removed our transgressions from us” (Psalm 103:12). John uses a word for forgiveness which has as its root meaning the notion of “sending away.” When we confess our sins, God removes our sins from his sight so that He does not focus on them; they have been paid for by the atoning sacrifice of Jesus Christ (cf. 1 John 2:2). God then applies to us the redeeming work of Christ. There is the reassuring aspect of finality in that word forgiveness.

And God purifies us from all unrighteousness when we confess our sins. He washes us so that we are clean. When we are forgiven, our robes are white because they have been washed in the blood of the Lamb (Revelation 7:14). We are then whiter than snow, not by nature but by virtue of Jesus Christ’s work.

God looks at us as we are through faith in Jesus Christ. When we confess our sins, we are forgiven and purified people. That is a matter of God’s covenant faithfulness and justice!