What does 1 John chapter 4 mean?

Chapter 4 includes two major ideas. The first is that believers ought to "test the spirits" to see whether they are from God (1 John 4:1–6). The second theme is that God both loves us and "God is love" (1 John 4:7–21), leading believers to love one another.

First John 4 begins with the command to test spiritual claims, since not all teachers are true to the faith. Christians are never instructed to believe "just because." In fact, we are often warned to carefully consider before we trust any particular message (Acts 17:11; Colossians 2:8–10). John was concerned that false prophets and false teachings would deceive his readers. First John 4:2 gives the test for spirits which actually come from God. These are those that acknowledge Jesus Christ's real incarnation.

John adds that believers overcome the powers in this world because of God's Spirit within them (1 John 4:4). "The world" refers to godless humanity. A worldly attitude listens to unbelievers and ungodly spirits, and ignores God.

The second major section returns to the idea that "God is love." John teaches that biblical love is a sign of being born of God, and knowing God. He states emphatically that believers are to show their love for God by loving one another (1 John 4:7–12). Love not only demonstrates God's presence in our lives, it serves as evidence to the rest of the world. Love is how the world is meant to "see" God, even though they cannot do so physically.

Verses 13 through 21 can be summarized by the final verse. Anyone who claims to love God must prove it by loving his brother. John's teaching repeatedly emphasizes the fact that a person cannot claim to love God yet hate others. As chapter 3 made clear, hate is always from a demonic source. Those who hate are not "abiding" in Christ. Believers are children of God and brothers and sisters of one another. As family, they are to love one another according to the commandment of God.

Verse 18 offers an important perspective on the relationship between love and fear. Namely, that godly love and worldly dread are incompatible. God's perfect love drives out fear about being accepted or rejected by Him. Other places in Scripture speak of "fearing" God in the sense of awe, respect, or trembling before Him. Here, however, John's focus is on anxiety over whether or not God will truly love and forgive us. Believers who follow God's example of love have no reason to fear that God will not accept them. His perfect love removes the need of this fear. God is love, shows perfect love, and places love in the hearts of those who believe.