1 John is all about abiding in God. Jesus used the same phrase in his prayer in the Garden. He wants us to abide in him just as he abides in the Father. So if we abide in God, we become his sons, we are begotten of God. As sons, we inherit eternal life, we walk in the light, we are no longer blinded by the darkness. Through our sonship we conquer the world–that is, the fleshly desires of concupiscence and the temptations that surround us. As sons, we have fellowship with God and with his other sons–the brothers, the Christians. Now the only way that this amazing sonship, this awesome “abiding” is available is through Jesus. John defines love as laying down your life. That’s exactly what Jesus did for us. Now, we haven’t personally seen his life, but John did. We have heard his testimony by reading his Gospel, so we have heard God’s promises to us. And God’s promises are always good. So because of Jesus, we have received eternal life, fellowship with God, sonship as God’s sons, fellowship with each other.
Since we have received all of these amazing gifts, our behavior patterns must change. That is, we must stop sinning, because we are no longer children of the devil. We are now children of the light. Darkness and light don’t mix. Our very nature has been uprooted and replaced with a “son of God” nature. It is no longer natural for us to sin. It doesn’t make sense because it contradicts our very own nature as sons of God. So, we know we are sons of God if we stop sinning and start loving our brothers in Christ. These behavior changes are evidence of our conversion. You might not be convinced that you’re a son of God, but God is! He has died for you so you could be his son. He has welcomed you into the family.
Now, if we still sin and hate our brothers then our conversion is not complete. John compares someone who hates his Christian brother to Cain who was the first murderer ever. John equates hatred and murder, just like Jesus does in the Sermon on the Mount. John also advises his readers on how to “test spirits.” That is, sometimes we think we are hearing God, but it really is a demon trying to mess with us. If you’re not sure whose voice you’re hearing, simply ask it if Jesus came in the flesh, died and rose again for the whole human race. If the voice acknowledges Jesus, then it’s from God. If not, it’s from the devil or the flesh. You see, demons can speak to us, but we can also produce “voices” with our own mind and desires. It’s simple psychological projection. For example, if you really want something, you could start telling yourself that God wants you to have it, when really it’s just something you want.
In sum, God has freed us from sin and death by the suffering, death and resurrection of Jesus. We have received this great grace through faith and baptism, so now we are sons of God, begotten of God. We abide with him and we are no longer blinded by the darkness of sin. We walk in the light because we have heard the promises he gave to us. We are now ready to conquer the world and inherit eternal life.