So we are lying if we say we have fellowship with God but go on living in spiritual darkness; we are not practicing the truth. But if we are living in the light, as God is in the light, then we have fellowship with each other, and the blood of Jesus, his Son, cleanses us from all sin. 1 John 1:6-7 NLT
John, from the previous passage, describes Christians as having fellowship with the Father and the Lord Jesus Christ. Real fellowship speaks of intimately sharing and “living in the light.” There is nothing hidden in the presence of God. This is why a child of God who walks in the fellowship with God means he or she should conduct his or her life that manifests godly living. It is a lie if he or she refuses to live the way God wants them to live. John was writing to a group of people near the end of the 1st century claiming that they are in fellowship with God but their actions are inconsistent with their claim. Conduct and word should be in agreement in the life of a believer. Our deeds should be able to stand when exposed to His light. “And the judgment is based on this fact: God’s light came into the world, but people loved the darkness more than the light, for their actions were evil…hate the light and refuse to go near it for fear their sins will be exposed. But those who do what is right come to the light so others can see that they are doing what God wants” (John 3:19-21). Continually or prolonged living in darkness can lead to blindness. This blindness leads to refusal living in accordance with God’s Word and precepts. Life is set against God and His will is disobeyed. It fosters confusion instead of harmony; it produces discord instead of peace; instead of fellowship there is enmity. Once we have real fellowship with God, His grace displaces the darkness and He fills our lives with His light. When we have fellowship in the light of God, “we have fellowship with each other.” We continuously conduct our lives staying in the direction He had set for us, relying in the radiance of His light. This results in reflecting God and the glory He possess. This life of fellowship provides longing to be in the body of believers for in their fellowship with one another, the heavenly presence of God is being magnified. It is the “blood of Jesus, his Son” that “cleanses us from all sin.” This is what strengthens the fellowship with God and with one another; the knowledge that our sins are forgiven by the blood of our Lord and Savior Jesus Christ.