Fellowship Enables to Overcomes the world: 1 John 5:1-5.  
Everyone who believes that Jesus Christ has come in the flesh is born of God. Biblical faith is not an intellectual assent of some biblical facts but the total commitment to Jesus Christ.  They are persuaded of the historical account of Christ trustworthy and believe in him. True believers love God and fellow believers.  They do not feel it burdensome because they are characterized by the desire to obey God. Faith, love and hope in Christ always go together. Jesus told His disciples “If you love me, you will keep my commandments” (John 14:23).  Faith, in Christ, love for others motivates believers to live in obedience to God (5:1-3). Everyone born of God will overcome the world through faith in Christ. This is the saving faith that believes that Jesus is the Son of God. Only Christ enables believers to overcome the world (5:5).  Some hope to make a better world. Others are trying to get to heaven by living a good life.  The Bible says we are saved by the grace of God. We cannot take credit for salvation because it is a gift of God.  The Bible teaches that there is no salvation outside Christ. Any attempts to cast doubt on the sufficiency in Christ must be rejected. Believers are  constantly facing the enticement from the world, the Satan and the flesh. The lust of the flesh, the lust of eyes and the pride of life are real  (1 John 2:16).  It is easy for us to yield to these temptations and hard to keep our minds pure. Satan will do whatever it takes to lure us away from God.  We are no match for Satan.  When we face temptation, Christ is our strength (2 Corinthians 12:9).  He is able to keep us from the wicked one (James 4:7). The divine nature we received enables us to stand against the lure of Satan (1 John 5:18; Luke 22: 31, 31; 1 Corinthians 10:13). The victory that overcomes the world is our faith in Christ.

Jesus is the Son of God: 1 John 5: 6-10. 
Jesus Christ was revealed as God’s Son by his water baptism and by shedding of his blood on the cross. The Holy Spirit also testifies that Jesus is the Son of God.   False teachers taught that Jesus was merely a man on whom “the Christ had come on at His baptism and left him before crucifixion”.  Scholars suggest that the water is a reference to Christ’s baptism and the blood is a common symbol of His death.  At His baptism we see Father’s attestation of His Son and the descending of the Holy Spirit upon Jesus (Matthew 3:13-17).  "This is My beloved Son , in whom I am well pleased".  When Jesus died on the Cross, Roman centurion testified of Jesus that “ Truly this was the Son of God” (Matthew 27:54).  By resurrection, the Father confirmed Jesus as the Son of God (Romans 1:4). The Spirit bears witness in the believer’s heart that we are the children of God (Romans 15:15-16).  Scripture teaches that by the witnesses of two or three, a matter can be settled (Deuteronomy 19:15). Rejecting the witness of God makes Him a liar.

Assurance of Eternal Life: 1 John 5:11-13.   
The message of the letter is that God has given us eternal life and this life is in His Son.  Eternal salvation is not gained by human effort but is granted to those who trust in Christ.  Whoever has the Son has life and he who does not have the Son of God does not have eternal life.  John wrote the gospel so that we may believe that Jesus is the Christ and be saved (John 20:21).  But John wrote the epistle to those who believe in the name of the Son of God, so that they may know that they have eternal life (5:13). The eternal security of salvation is based on the finished work of Christ (John 19:30; Hebrews 10:14). It is the fundamental nature of God’s salvation (John 5:24). The intercessory ministry of Christ guarantees eternal salvation (Hebrews 7:25).   God’s unfailing promises guarantees eternal salvation (John 10:27-29). If eternal life can be lost, it is the wrong name used in the Bible.  This confident assurance in eternal life should be manifested in their daily life.  Their lives should be characterized by righteousness and love for God and the brethren. They overcome the world through faith in Christ (1 John 3:9; 3:14; 5:4). They do not habitually practice sin because they have a new nature (1  John 3:9). They will turn away from false gods.

Fellowship gives Assurance of Answered Prayer: 1 John 5:14-17.  
Believers who remain in fellowship have the confidence that God would answer their prayers. God is our heavenly Father whose ears are opened to our prayers (1 Pet 3:12). Our confidence is that God will give us what we ask for according to his will (1 John 5:14-15). Prayer is an exercise in which his Spirit enables us to move ourselves according to God’s will. The scriptures reveal God’s will. Prayer is not overcoming God’s reluctance but it is laying hold of his willingness.  There is a sin that leads to death and we should not pray for that (1 John 5:1:16). Bible teachers differ on the interpretation of this verse. Some think John is talking about the sin against the Holy Spirit. Keeping the context in mind we can conclude that this is the sin that leads to premature death of the apostate.  Apostate is the one who heard the gospel and made up  his mind to reject Christ and the free gift of salvation. They are professing Christians who are not saved (2:19). They had known the facts of the Bible but they willfully deny the deity of Christ and the sufficiency of his atoning death to save them. Apostates misinterpret the grace of God and choose to live in sin.  God's grace is not a license to live a sinful life. People who had sinned willfully died because of their sin in the Old Testament (Leviticus 10:1-7).  When believers do not confess and forsake their sin, they will be disciplined (Heb 12:1-13).   If they continue to live in sin they may die premature death (Acts 5:1-11; 1 Corinthians 11:30).  Our God is a holy God and He will not allow His name to be disgraced.  We are saved by the grace to live a holy and blameless life.  Christians must not take God’s grace for granted to live a life of sin. To whom much is given, much shall be required.    

Conclusion: 1 John 5:18-21.  
John concludes that whoever is born of God does not practice sin because he has a divine nature. They are kept by the divine power of God through faith for the salvation revealed on the last day (1 Peter 1:5; Jude 24, 25; John 10: 28).  We have no power within us to protect us from the devil. But as we keep ourselves in the love of God and meditate on His Word, we will have victory over sin (Psalms 119:11).  False teachers are under the control of the evil one and their lives are characterized by sin.  Believers know that they are born of God and have personal relationships with Christ. The purpose of writing this epistle was to give assurance of eternal life to believers (5:13).  Christ came to reveal the true God.  God the Father can only be known through Jesus Christ (John 1:14, 18). Jesus Christ is the only true God and he is the source of eternal life (5:20).  The whole world is influenced by the evil one. Christians do not need to live in fear because Christ is on their side.  Believers must be on guard against false teachers.  Do you have the assurance of salvation through Christ?