John’s first letter shares his testimony about Jesus Christ and its impact on Christians. Jesus Christ offers eternal life, so we can know through our actions and experiences that we have eternal life. Jesus reveals God the Father, giving us confidence in our relationship with Him.
Jesus gives the Holy Spirit to everyone who is spiritually born. This allows us to live daily in the Spirit. Just as Jesus called his first disciples to love one another, John encourages Christians to show that love in action.
Setting
John and the other apostles probably had to leave Jerusalem by AD 68, or earlier. This was because abuse increased against the church and the Romans attacked Jerusalem. Later, probably after AD 70, John moved to the Roman province of Asia, now the western part of modern Turkey. He started a successful ministry, mainly among the gentiles (non-Jewish people). By AD 90, John had written his gospel for these Christians.
Soon after this, some members of the Christian community left to form a rival group. This group was a heretical faction (false teachers) that spread ideas about Jesus Christ which opposed the teaching of the apostles. For example, they denied that Jesus was truly God in human flesh (see 1 John 4:1–3). These wrong teachings later became known as Gnosticism. Gnosticism is a religious system that values hidden or secret knowledge instead of faith in God.
By leaving the fellowship of the apostles, these rivals showed that they were not truly part of God’s family (1 John 2:18–19). However, their false teachings still affected Christians. So, John wrote this letter to correct these lies, guide Christians back to the basics of Christian life, and strengthen their faith.
John may have confronted the heresy promoted by Cerinthus, a leader of Gnostics with some Christian beliefs. Cerinthus taught that Jesus was not born to a virgin. Instead, Cerinthus said Jesus was a regular human born to Joseph and Mary. He believed Jesus was simply more holy, sensible, and wise than others. Cerinthus also claimed that at Jesus's baptism, "the Christ" descended on him like a dove from the eternal Father.
"The Christ" then revealed the unknown Father and performed miracles. Eventually, "the Christ" left the man "Jesus," who then suffered and died. "The Christ" remained without change, since he was a spiritual being. John may be directly challenging the heresy of Cerinthus or his followers in 1 John 5:5–8.
He sent this first letter to the churches under John's care (including those mentioned in Revelation 1:11) around AD 85–90.
Summary
John wrote this letter to encourage Christians in the Roman province of Asia to remain strong in their faith in Christ. He criticized those who had left the community and the teachings of the apostles. John stressed that Christians must remain loyal to Jesus's apostles. These were those who followed Jesus (the disciples) during his life and knew him personally. Dedication to the apostles would protect against false spiritual ideas and heresy.
John urged his Christian readers to:
remain loyal to the apostles. In doing so, they would unite or have fellowship with God, who is light, by living in the light he provides;
confess their sins to God to receive the support and guidance of Jesus Christ, the righteous one;
honor Jesus Christ as the Word of life and the Son of God;
love God, who is love, and love other Christians;
remain in Christ, become like Christ, and spiritually clean themselves of the desires of this world;
personally know and experience God and understand his truth through the Holy Spirit;
identify false teachings with the help of the Holy Spirit. Recognize the spirit of false prophets and the antichrist (someone who denies Jesus is the Christ); and
be confident in the hope of eternal life.
Author
Some scholars suggest that a Christian elder named John, not the apostle, wrote 1–3 John (see 2 John 1:1; 3 John 1:1). They base this idea on a quote from Papias (bishop of Hierapolis in Asia, AD 100–130). Papias mentioned John the apostle and later mentioned John the elder:
"If I met someone who followed the elders, I would ask about the elders' words—what Andrew, Peter, Thomas, James, John, Matthew, or any other of the Lord’s disciples had said. I would also ask about what Aristion and the elder John, the Lord’s disciples, are saying." (Eusebius, Church History 3.39.4)
This quote has led some to think Papias was talking about two different people named John. But that is not necessarily true. Papias noted what the “elders” (including the apostles like John) had said (past tense) about Jesus and what two of the Lord’s disciples (Aristion and John) were still saying (present tense). The apostle John lived to be very old (an elder), and Papias heard him speak in person.
Most conservative protestant scholars believe John the Apostle and John the Elder are the same person. The writing style of John's Gospel is very similar to that of these three letters. The Apostle John was a personal witness to Jesus and among the first to follow him. In John's Gospel, John is called "the one whom Jesus loved" (John 13:23; 19:26; 20:2; 21:7, 20).
He was one of the twelve disciples and a close friend of Jesus. The author's claim to be an personal witness is as strong in the letters as it is in the gospel (see 1 John 1:1–4; John 1:14; 19:35). The author of 1 John claims to have personally heard, seen, and touched the eternal Word (Greek logos) made flesh (1 John 1:1–4). It is reasonable to conclude that the "elder" of 1–3 John is the Apostle John.
Meaning and Message
John’s first letter continues the themes and teachings from his gospel. The Gospel of John shows that Jesus's mission was to reveal God the Father. He also came to unite Christians with the Father and the Son through the Holy Spirit. John’s first letter emphasizes how Christians experience God daily through their relationships with other church members.
We must show our love for God by loving one another. Jesus directly gave this command (John 13:34; 15:17). John repeats it often (1 John 2:7; 3:11, 23; 2 John 1:5–6). Since God is love, everyone who claims to know God must love others.
Loving other Christians does not mean accepting everything they say. Nor does it mean accepting what all that independent teachers say. Some people left the Christian community. They denied that Jesus is the Christ, the unique Son of God, or that he came as a human being.
Anyone who denies that Jesus Christ was fully human and fully God is an antichrist. This letter strongly warns against those who teach such heresy. It also warns against those who lead Christians away from fellowship with the true apostles of Christ.
History shows that many false movements have entered the church. But the truth has survived these attacks. We must be cautious of teachings that oppose the apostles' teachings. The word of God and the Holy Spirit guide us.