“If we say that we have no sin, we deceive ourselves, and the truth is not in us.”
and the truth is not in us
Self-deception arises from openness to false teaching (2:18,26; 3:7; 4:3,6). Christians constantly face frontal attacks from the demonic world of false teaching. Those who bite on false teaching render their Christian lives weak and dull.
Self-deception preempts truth as an efficacious principle in our lives.
Truth in the Bible is more than flat or abstract ideas about the Bible because biblical truth requires an engagement of what we believe with our lives. We live out the truth by believing the truth, doing the truth. If we deceive ourselves, the truth cannot be in us. It shuts out the truth. If truth truly rests in us, it exposes the awfulness of our sin so that we cannot lightly explain it away.
Just because we are not aware of sin in our lives, that does not mean that we are free from transgression. A Spirit-filled believer does not deceive himself. He is radically honest with himself for fear that he might step out of favor with God.
We need to discover the power of biblical Christianity again. When we walk with God based on truth, we live in the power of God. Christianity is primarily a relationship, not a religion. When a Christian steps out of fellowship with God, he loses the vitality of Christianity. He no longer has the power for living he once had. His Christianity becomes orthodox, dull, and dead. He deceives himself that he walks with God.
Believers who walk in integrity do not hide their sin but face it and admit it. God wants us to call sin for what it is (1:9). He wants us to admit our need for the blood of Christ to cleanse us from our sin. Sensitivity to truth always makes us more aware of personal sin.