1 John 2:4 ⁴The one who says, “I know him,” but does not keep his commandments, he is a liar, and the truth is not in this one.

John next addresses the issue of fooling oneself into thinking one is a genuine Christian while not living like one. He follows his pattern by stating a condition, followed by giving its result if true. People may claim they know Jesus, but their knowledge is only fragmentary or intellectual. Genuine knowledge comes with experiencing a person in relationship. The crucial part of knowing Jesus is obeying his commandments. The verb know (engnōka) is in the perfect tense, implying that such a person has had time to get to know Jesus but has failed to do so by ignoring what Jesus said. This person has fooled himself or herself into thinking they are right with God but has ignored the Holy Spirit’s conviction of sin.

Jesus said in Matthew 7:21, “Not everyone who says to me, ‘Lord, Lord,’ will enter the kingdom of heaven, but the one who does the will of my Father who is in heaven.” Obedience is not optional for Christ followers. Knowledge comes through obedience because obedience brings deeper understanding of who God is and how we must interact with God. Obedience moves knowledge from the head to the heart. Obedience is the key that opens the door to transformation. Obedience to Jesus’ commands turns knowledge about Jesus into knowledge of Jesus, which is faith. Obedience changes our thinking so that we take on the mind of Christ. We become like the one we follow. If we follow Jesus, then we will become like him. We fool ourselves and have no truth in us if we think that being a Christian is only about mental faith or an outward confession of the mouth. If the lifestyle does not match the holiness of God, we are deceiving ourselves.