Fellowship with God made Possible: 1:1-4.
The epistle of first John begins with the historical account of the incarnation of Jesus Christ and the gospel. Christ who existed with God the Father from eternity has entered the human history as a real human being (1 John 1:1-2). God became a man so that the life that is in Christ Jesus might be made manifest. John has seen Jesus with his own eyes and associated with Him. All who receive this testimony may have fellowship with Him (1 Cor 1: 9). This fellowship is what Jesus prayed for when he was on earth (John 17:3). True joy only comes through relationship with Jesus Christ. These things are written that believers may fully share the joy apostles had. Joy is the fruit of the Holy Spirit (Gal 5:22). It is the by-product of our fellowship with God and other Christians. The world is not capable of providing this deep seated joy and satisfaction. God gives lasting joy which no one can take it away ( Heb 11:25; Psalms 16:11). The Apostles were not ashamed of sharing this wonderful news. The foundation of Christian fellowship is the person of Jesus Christ. Christian fellowship is not sitting around a table and sipping coffee. Fellowship means joint participation and having things in common. Those who are saved are the partakers of His divine nature. Man is lonely without God. God wants to fellowship with us always. Jesus made it possible by His presence with us (Matt 28:20). John explains the secrets of fellowship with God and with other Christians in his letter. Someone has said “Fellowship is two fellows in one ship”. The gospel is the goodness of great joy. It is the good news of what God has done to rescue us from sin.
The Basis of Fellowship: 1:5, 6.
Christian fellowship starts with communion and partnership with Christ. John gives two word pictures for moral purity and evil here. God is light and in him is no darkness at all. God is absolutely righteous and there is not even one bit of darkness in Him. A person who says he is saved and habitually live in sin is lying and he is not in fellowship with God. False teachers claimed that they were in fellowship with God and at the same time continued to live according to the world standards. John concludes that it is impossible. Christians are cleansed by the blood of Christ and have a new nature. Since we have been cleansed by the blood of Jesus Christ we can live in righteousness and have fellowship with God and fellow believers. What makes the difference is the atoning death of Jesus Christ for our sins. Fellowship here refers to being born again. Sin is a fact of life and it must be dealt with (1:8). To walk in darkness means to live a life apart from God, who is the light.
How to deal with Sin: 1:7-10.
The correct way to deal with the sin is not to deny it, but to confess it and allow God to cleanse us. Confess simply means to acknowledge or agree with God when Holy Spirit convicts us of our sins. When we confess our sins, God is faithful and just to forgive our sins and to cleanse us from all sin (1:9). God is faithful to forgive us our sins and also to cleanse us from all unrighteousness (Psalms 130:3-4). When God says He forgives our sins, we must be willing to forgive ourselves. Sad to say some find it difficult to forgive their past sins after being saved. If we claim we have never sinned, we make God a liar and His word is not in us (1:10). It is the willful denial of the very reason Christ came to suffer and die for us. Christians are the dear children of God and they should reflect Father’s character in this wicked world. God’s standards are perfect and He cannot condone sin. He knows our nature and made provision for our weaknesses (Psalms 103:14; 1 Cor 1:13). In this passage John reminds us that when we do sin, the blood of Jesus his Son cleanses us from all sin (1:7). Jesus paid the penalty of our sins. His death is sufficient to save the whole world but is efficient to save those who believe in Him. Someone has said "In salvation the initiative, conviction and revelation come from God. All that we contributes toward salvation is our sin". God is faithful in his promise to forgive our sin as we acknowledge our sin and believe in Christ. So people need to hear the good news of His saving grace, the gospel. To live in fellowship means to be honest with God and with ourselves. Ask God to protect you from living in the darkness of sin. Confess your sin and embrace the forgiveness promised to you in the Lord Jesus Christ.