1 John 1

That which was from the beginning: This means Jesus existed before time began and is eternal (John 8:58). When Jesus became a human, the apostles gazed upon and touched him (John 1:14). This statement is important because some early groups, such as Gnostics and Docetists, denied that Christ was truly human (see 1 John 4:2–3). These groups taught heresies (false teachings) about Christ

Jesus, the Son of God, is the personal expression of the invisible God. He is the giver of eternal life (John 1:1–4).

• This opening section, written in the form of a poem, is similar to the message of the beginning of John’s Gospel (John 1:1–18).

• The we language in the introduction refers to John and the other apostles, and perhaps to other Christians who had seen and touched Jesus Christ. The apostles personally saw Jesus and had personal fellowship with God through him. John, representing the apostles, now invites those he is writing to join in that fellowship.

• This is the life: Throughout the New Testament, the Greek word zōē (which means "life") is used to describe God’s own eternal life (for example, Ephesians 4:18). This life is found in Christ, and he gives it to all who believe in him.

• this is the life that was revealed to us: Jesus, the Christ, was known to his apostles as a human being during his earthly ministry.

• What we have seen: The Word of life had, as a human being, revealed God to the apostles.

• this fellowship of ours is with the Father and with His Son: After the Spirit gave the apostles new life (regenerated them), they entered spiritual fellowship with the Father and the Son.

• you also may have fellowship with us: Whoever entered into fellowship with the apostles by associating with them while they were alive, or enters now by remaining in their teaching, has fellowship with the Father and the Son through them.

so that our joy may be complete: The joy that the apostles have comes from their fellowship with God the Father and the Son (1:3). Those John is writing to will share this joy when they also enter into this close relationship with God.

God is light: This means that God is completely pure, good, and true. When Jesus Christ lived on earth, this light shone through him to everyone he met. His life exposed the sin in people’s hearts, because his words and actions showed God’s perfect standard. At the same time, his light also helped people understand what God is really like—his goodness, his mercy, and his desire for people to walk in truth (see John 1:4–5, 9; 3:19–21; 8:12; 9:5; 12:35–36, 46).

In the writings of John, “light” stands for God’s holiness and his clear revelation of what is right. “Darkness” refers to false teaching and to living without self-control or obedience to God. These two ways of life cannot mix. People who walk in the light live in the truth of God. People who walk in darkness follow what is false and harmful (1 John 1:6).

Here John focuses on the first part of living in fellowship with God. To live in the light means that Christians see that they are sinners. It also means they understand that Jesus is their Advocate, the one who speaks for them and makes them right with God (see Ephesians 5:6–13).

This is the first of several times when John challenges the claims of the Gnostics. These teachers had separated themselves from the fellowship of the apostles, so they were living in spiritual darkness. They claimed to have fellowship with God, but they did not show God’s character, which is light.

Jesus warned the Jewish leaders of his day not to let the light they believed they had become darkness (Matthew 6:23). Their religious beliefs kept them from receiving the true spiritual light that Christ offered. In the same way, the Gnostic teachers believed they were enlightened, but their teachings actually led them into darkness.

They claimed to receive spiritual experiences from God. Yet they rejected fellowship with the apostles, who had truly seen God in the flesh in the person of Jesus Christ.

Christians share fellowship with each other and with God when they live in the light. A person cannot claim to have fellowship with God and then refuse fellowship with God’s people. This was the behavior of the Gnostics. The apostles of Christ had known Jesus Christ as God in the flesh, and they continued to have spiritual fellowship with him (1:3).

If we say we have no sin: This is the second false claim of the Gnostics (see 1:6). They trusted they could be free from sin because Christ had removed their sins forever. They believed that their special knowledge put them in a position where sin no longer mattered. But Christians do still sin when they live in their old nature (see Romans 7:14–25). A true Christian both acknowledges this sin and trusts Christ to take it away (1 John 1:9).

To stay in continual fellowship with God, we need to confess our sins to him. God promises to forgive and cleanse us, and we can trust this promise because God is faithful and just. Christ died for our sins, and his death satisfies God’s justice and removes our guilt.

If we say we have not sinned, we make Him out to be a liar: God's word highlights how sin affects everything deeply (see study note on 1:8).