One assurance of God's Holy Spirit among believers is God's love expressed to each other. Believers love because He first loved them, and those who truly love God cannot hate their brother (1 Jn 4:19-20). God's divine love enables believers to reject hatred and practice love for their brothers (and sisters). Therefore, every true believer will value the church community. The apostle would remind the readers of remaining true to the doctrines they have learned. John would explain that being born of God, loving God, loving the community, and remaining true to the doctrines are all intertwined.

The author explained that God is love. The Father manifested His love by sending His Son, who became the propitiation for our sins. God is the very reason why we should love one another. John would continue to emphasize that if believers truly love God, they would love one another. If believers do not love the community of faith, they are not true believers in Christ.

After instructing the believers to test the spirits, meaning to test every proclamation or influence, the apostle mentioned love more than 40 times in this letter. It is about God's love and the believers' love for each other. The emphasis reveals to us its importance. The community of faith must practice love for each other. Rejecting false teaching and loving the brotherhood go together in the life of the church community.

The apostle explained that the Holy Spirit leads the believer to believe in Christ and to love one another. Such is made possible by the Holy Spirit's work. Those who are in the light fellowship with the Father, Son, and Spirit (1 Jn 3:23-24). John proceeds to warn believers to exercise spiritual discernment. They should test the spirits, because there are many false prophets. Believers can take comfort in knowing that they are from God and have overcome the false teachings of these teachers. The Spirit who dwells in the believer is greater than the one who is in the world. False teachers speak from a worldly perspective and are accepted by the world, but those who are from God listen to the apostolic message. This is how believers can distinguish between the Spirit of truth and the spirit of error.

John stated that those who practice sin are children of the devil. Anyone who makes sin a lifestyle, meaning, habitually practicing it intentionally, is not from God. The author emphasized that those who deviate from the teachings of Christ revealed by the apostles do not belong to God. But those who believe that Jesus is the Christ, meaning Messiah, the promised One, and the only Savior, are from God. Their knowledge of God makes them keep His commandments. Genuine believers are born of God, which means they have a new life in Christ. In doctrinal terms, it is referred to as regeneration. True believers do not love the world. Genuine believers do not hate like Cain, for hate is murder; instead, genuine believers love in deed and truth. This is expressed through serving one another and giving to each other, especially in times of need. The author's words hit hard throughout the letter; they were sharp and uncompromising. Anyone who reflected on the apostle's words might feel condemned. If so, John gives comforting words. God is greater than our condemned hearts.

John reminds believers of the foundational message they have heard from the beginning: to love one another. He contrasts the love of believers with the hatred of the world, using Cain as an example of unrighteousness and murder driven by jealousy. John warns that hatred is incompatible with eternal life and equates it with murder in the heart. True Christian love, by contrast, is the mark of those who have passed from death to life.

John shows a clear divide between the children of God and the children of the devil. Sin is lawlessness. Jesus came to take away sin and destroy the devil's work. Those who belong to Christ do not keep on sinning. A true believer cannot live in habitual sin. Righteousness marks the one born of God. So does love. Our actions reveal who we truly belong to. John continues by showing that love is the core command of the Christian life. He contrasts love with hatred using the example of Cain.

The children of God belong to God. They do not belong to the world. If they loved the world and its ways, then the love of the Father is not in them. They are not genuine believers. Genuine believers know God, and they keep His commandments. They love fellow believers, and they do not hate, for hate is darkness. All who have the hope of eternal life purify themselves because Christ is pure. 1 John 3:3: And everyone who thus hopes in him purifies himself as he is pure. John would continue to remind them that those who abide in Him do not have a sinful lifestyle. Those who practice a continuous pursuit of sin are of the devil.

The apostle warns believers that they are living in the “last hour.” One evidence is the presence of many antichrists, false teachers. These individuals seemed to be part of the community but ultimately departed. It proved that they did not truly belong. In contrast, true believers received an anointing from the Lord. The anointing signifies the knowledge of the truth. John calls the readers to remain grounded in the truth. The apostle reassures believers that they know the truth and can discern lies, particularly those that deny Christ Jesus.

The apostle warns believers that they are living in the “last hour.” One evidence is the presence of many antichrists, false teachers. These individuals seemed to be part of the community but ultimately departed. It proved that they did not truly belong. In contrast, true believers received an anointing from the Lord. The anointing signifies the knowledge of the truth. John calls the readers to remain grounded in the truth. The apostle reassures believers that they know the truth and can discern lies, particularly those that deny Christ Jesus.