Verse 10: Devoid of the Word
10 If we say, “We have not sinned,” we make him a liar, and his word is not in us.
This verse unfolds the final antithetical statement that opposes the phrase “God is light”; if we have never sinned, God’s actions towards us are not love. If we have not sinned, there is no light in God when he forgives our sins and punishes the sins of the unrepentant.
God mercifully forgives the broken-hearted:
Romans 2:4 (CSB) Or do you despise the riches of his kindness, restraint, and patience, not recognizing that God’s kindness is intended to lead you to repentance?
Psalm 51:17 (CSB) The sacrifice pleasing to God is a broken spirit. You will not despise a broken and humbled heart, God.
God punishes unrepentant sinners:
Romans 2:5 (CSB) Because of your hardened and unrepentant heart you are storing up wrath for yourself in the day of wrath, when God’s righteous judgment is revealed.
“We have not sinned” makes both God’s mercy and justice a lie because God cannot mercifully forgive those who have never sinned, and he cannot be just if he punishes the sinless.
This phrase actively denies both dimensions of human sin:
Sin Nature:
Romans 5:12, 18-19 (CSB) Therefore, just as sin entered the world through one man, and death through sin… 18 So then, as through one trespass there is condemnation for everyone, so also through one righteous act there is justification leading to life for everyone. 19 For just as through one man’s disobedience the many were made sinners, so also through the one man’s obedience the many will be made righteous.
This dimension of human sin refers to our unholy natures that were defiled when the separation of the human race from God occurred because of Adam’s sin. Death reigns over humanity because we are fundamentally separated from God by our defiled natures.
Sin-Guilt:
Ephesians 2:1-2 (CSB) And you were dead in your trespasses and sins 2 in which you previously lived according to the ways of this world, according to the ruler of the power of the air, the spirit now working in the disobedient.
This dimension of human sin refers to our spiritual deadness that is the result of our conscious rebellion against God. Whereas our physical deadness came from our defiled natures that we inherited from our human parents, our spiritual deadness comes from our active and conscious transgression of God’s character.
This denial rejects both our sin-nature and our sin-guilt.
“And his word is not in us” renders the terrifying indictment that the word of life does not indwell those whose hearts are still hard to the severity of their sin. “The word” is not a reference to intellectual retention of Scripture – John is not simply saying these people have never heard the word – but refers to the life-giving presence of the Holy Spirit living in us:
John 6:63 (CSB) The Spirit is the one who gives life. The flesh doesn’t help at all. The words that I have spoken to you are spirit and are life.
The person who says “I have not sinned” can only make this claim because they do not have the light of life dwelling in them. They can only make this claim because they are still hiding in darkness and have not come into the light; only in the darkness can we deny both our unholy natures and our personal guilt.
Biblical Reasons 