Resource Detail

2026 1 John Lesson 1

TRUE CHRISTIAN FELLOWSHIP

1 John 1:1-10

Key Verse: 1:3

1. Why does John emphasize that he has “heard,” “seen,” and “touched” Jesus (1)? Who is “the Word of life,” and what does it mean that “the life appeared”? What does this passage teach about the identity of Jesus?
2. What purpose is given for their proclamation (3)? What are the characteristics of Christian fellowship? How is joy connected to this fellowship (4)?
3. What does it mean that “God is light” (5)? Why does John say that claiming fellowship while walking in darkness is a lie (6)? What is the relationship between walking in the light and fellowship with one another (7)?
4. What do people claim about sin, and what are the consequences (8-10)? What does God promise to do when we confess our sins (9)? How can we build deeper and more honest fellowship with others?

2026 1 John Message Juan Seo (April 19, 2026)

TRUE CHRISTIAN FELLOWSHIP

1 John 1:1-10

Key Verse 1:3

We proclaim to you what we have seen and heard, so that you also may have fellowship with us. And our fellowship is with the Father and with his Son, Jesus Christ.

Last weekend, we had such a grace-filled Spring Retreat. The grace we received during this Spring Retreat was so abundant that its impact is still with us even now. I especially want to express my heartfelt thanks to the three messengers who shared such powerful messages and life testimonies. I thank God that each one of us had the opportunity to come before Him honestly—to confess our sins, to lay down the burdens of our hearts, and to experience His unfailing love. Through that, we were invited into deeper fellowship with God the Father and with His Son, Jesus Christ.

The title of today’s message is “True Christian Fellowship.” Let me ask you—what does true Christian fellowship mean? In the New Testament, the word for fellowship is the Greek word koinonia. Many of you may have heard this word before. Koinonia carries a rich meaning. It means sharing, participation, partnership, and communion. So fellowship is not just “being together.” It means sharing life together. Based on today’s passage in 1 John 1:1–10, I would like to share three key aspects of true Christian fellowship with you.

First, true Christian fellowship is grounded in fellowship with the Father and with His Son, Jesus Christ. Verse 3 says, “And our fellowship is with the Father and with his Son, Jesus Christ.” Christian fellowship is completely different from the kind of fellowship we find in the world. In the world, fellowship can mean spending time together, sharing common interests, or enjoying one another’s company. But Christian fellowship cannot be explained apart from God. True Christian fellowship begins with knowing God the Father and His Son, Jesus Christ. And the Holy Spirit opens our hearts, leads us to Christ, and connects us to God, the Father. Knowing God is more than knowing about Him in our minds. It means coming to know God in a real and personal relationship. The apostle John experienced a real and deep relationship with Jesus.

That is why he says in verse 1, “That which was from the beginning, which we have heard, which we have seen with our eyes, which we have looked at and our hands have touched—this we proclaim concerning the Word of life.” When John says “that which,” he is referring to the Word of life. Who is the Word of life? John 1:14 says, “The Word became flesh and made his dwelling among us. We have seen his glory, the glory of the one and only Son, who came from the Father, full of grace and truth.” So the Word is not just a message or an idea. The Word is a person. The Word is Jesus Christ, who came in the flesh. Therefore, when 1 John 1:1 speaks about the Word of life, it is pointing to Jesus Christ, who is the source of life. John heard the words of Jesus with his own physical ears. He saw Jesus with his own eyes. He was an eyewitness. And not only that—he even touched Him with his own hands. At the Last Supper, John was reclining next to Jesus. He even described himself as “the disciple whom Jesus loved.” John stayed close to Jesus. For John, Jesus was not abstract. Jesus was real.

There is a reason why the apostle John speaks so clearly and strongly—saying that he heard Jesus, saw Him, and even touched Him. When John wrote this letter, around AD 85 to 90, a Hellenistic philosophy called Gnosticism was spreading in the Greek world. The word “Gnosticism” comes from the Greek word gnosis, which means knowledge. This philosophy taught that salvation comes through secret spiritual knowledge. One of the main ideas in Gnosticism was dualism. They divided everything into two categories: good and evil. They believed that the spiritual world is good, but the physical, material world is evil. So for them, it was impossible to accept that God, who is perfectly good, would take on a human body, which they considered evil. Because of this, even some believers could not accept that Jesus came in the flesh. They claimed that Jesus only seemed to have a human body. They said that Jesus appeared to be human, but He was not truly human. So they denied the real, physical incarnation of Jesus.

But if we do not believe that Jesus came in the flesh, what happens to our faith? Then Jesus’ suffering is no longer real. His death on the cross is no longer real. And if that is the case, then Jesus could not bear our sins. He could not take upon Himself the full weight of our guilt. And He could not fully understand our human pain and suffering. In the end, the very heart of the gospel is shaken. The truth that Jesus died for our sins is no longer secure. And if that truth is gone, then the foundation of our salvation is also gone. So the apostle John boldly and clearly testifies that Jesus came in the flesh. How could he speak with such confidence? Because he had lived with Jesus. He had walked with Him. He had shared life with Jesus in a personal and real way. This was his own experience. No one could take that away from him. And because of that, there was power and authority in his testimony.

In the same way, those who have experienced a personal fellowship with Jesus can stand firm, even when false teachings come. When your faith is based on a living relationship with Christ—not just abstract ideas—you are not easily shaken. You can stand on the truth with confidence. Jesus ascended into heaven, and now He is seated at the right hand of God the Father. So today, we cannot see Jesus with our physical eyes. We cannot hear His voice with our physical ears. We cannot touch Him with our hands as the apostles did. But God the Father and the Son have sent the Holy Spirit to us. And through the work of the Holy Spirit, we can still experience Jesus personally. By the Spirit, we can hear God’s voice. By the Spirit, we can see Jesus with our spiritual eyes. By the Spirit, we can feel His presence in a real and living way.

Think about the apostle Paul. On the road to Damascus, he encountered Jesus as a great light and heard His voice directly. That encounter completely changed his life. In my own life as well, I have seen Jesus hanging on the cross, suffering for my sins during my prayers. Through the Word of God, I often hear His voice directly speaking to me. And through prayer, I continue to have fellowship with Him—bringing my life before Him, depending on Him, receiving assurance in my heart, and walking with Him by faith. True Christian fellowship begins with having a deep, personal relationship with Jesus through prayer, the Word of God, and worship. It grows as we meet Him daily in prayer, listen to His voice in Scripture, and respond to Him in our practical lives. It deepens as we make a decision, day by day, to live as His disciples—to obey His Word, to follow His leading, and to walk with Him in our everyday lives.

Have you begun this kind of true fellowship with Jesus? If you have, I encourage you to keep growing in that fellowship. I pray that your relationship with Jesus will go deeper and deeper. And if you have not yet started a personal relationship with Jesus, I invite you to come to God, seek Him, and meet Him personally.

Second, true Christian fellowship is a life that walks in the light. Please look at verse 5: “This is the message we have heard from him and declare to you: God is light; in him there is no darkness at all.” The apostle John teaches us who God is. He does not say that God is full of light. He says God is light, just as God is love. When God created the heavens and the earth, the very first words He said were, “Let there be light.” And there was light. God saw that the light was good. This shows us that God loves the light and has nothing to do with darkness. In Him there is no darkness at all. So what is light, and what is darkness? Light represents goodness, holiness, order, truth, and life. On the other hand, darkness represents evil, sin, disorder, confusion, falsehood, and death. Since God is light, those who belong to God are children of light. And as children of light, we are called not to walk in darkness, but to walk in the light. So when someone says, “I have fellowship with God,” but continues to walk in darkness, that person is not telling the truth. He is a liar.

In the darkness, we hide ourselves, we pretend, and we live like hypocrites. Let me ask you—do you feel more comfortable in the light, or in the darkness? Generally, children are afraid of the darkness. They imagine something scary, as Chucky might appear. That’s why so many horror movies take place at night, in the darkness. But as we grew older, we began to feel more comfortable in the darkness. For some people, staying in the darkness becomes easier than coming into the light. When they step into the light, they feel exposed. They feel uncomfortable, even anxious, as if everything about them is being revealed. I can relate to that. As I was growing up, I began to feel more comfortable in the darkness. I liked being alone. Looking back, it was because my heart was dark. So when I went to a church, I felt uneasy inside. Darkness is a power. It is the place where sin rules, where Satan works. Satan uses sin to darken our hearts and our lives. But God is light. And when His light shines into our lives, it drives out the darkness. It leads us out of the darkness and into the light. Jesus Himself said, “While I am in the world, I am the light of the world” (John 9:5). So those who have fellowship with Jesus do not continue to walk in darkness. They begin to walk in the light.

Verse 7a says, “But if we walk in the light, as he is in the light, we have fellowship with one another.” As we walk in the light, we begin to have fellowship with one another. We share life together with other believers. Christian faith is not meant to be lived alone. It is meant to be lived in a community. Some people say, “As long as I have my personal relationship with Jesus, that’s enough.” So they don’t think that fellowship with other believers is necessary. They have worship services online. They prefer to stay by themselves. But a healthy faith always leads to fellowship with other believers. When we are in Christ, we open our hearts and share life together. We share the love of Jesus with one another. That is a healthy Christian life. That is what it means to walk in the light.

Third, true Christian fellowship is a life with honest repentance for sin. Please look at verse 8. “If we claim to be without sin, we deceive ourselves and the truth is not in us.” In John’s time, some believers who were influenced by Gnostic thinking did not take sin seriously. They believed that sin belonged only to the body and that what they did in the body did not affect their spirit. So they thought, “Even if I sin physically, I am still spiritually okay.” That is a very dangerous way of thinking. And honestly, it doesn’t make sense. Our body and our spirit are not completely separate. They affect one another. When we sin, it weakens our spirit. And when our spirit becomes weak, we become more vulnerable to temptation. It becomes easier to fall into sin again. So the apostle John speaks very clearly to those who claim they have no sin, “You are deceiving yourselves.” And even more seriously, “the truth is not in you.” In reality, they were justifying their sin and even taking pleasure in it.

The apostle John encourages believers to live a life with honest repentance. “If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.” (9) This confession does not come from our own strength. It is the work of the Holy Spirit. The Spirit opens our eyes to see our sin. He convicts our hearts and leads us to confess. And when John says “confess,” he means more than just thinking about our sin quietly. It means to speak it—to bring it out into the open, to acknowledge it honestly before God. This confession is ultimately made to our Lord Jesus Christ. Jesus is the only mediator between God and us. He receives our confession, and He brings it before the Father.

And what does God do? God is faithful. That means God keeps His promises. Because God loves us, He forgives our sins. At the same time, God is just. He cannot ignore sin. Sin must be judged. But Jesus took all our sins upon Himself, and He received the judgment that we deserved. Because Jesus was judged in our place, we can be forgiven. The blood of Jesus has the power to forgive all our sins. “The blood of Jesus, his Son, purifies us from all sin.” (7b) And “He will forgive us our sins and purify us from all unrighteousness.” (9b) Because of the precious blood of Jesus, we are purified.

Our fellowship as believers is completely different from the kind of fellowships we find in the world. First of all, the relationship itself is different because it is based on our identity. When we are born again with the grace of Jesus and the work of the Holy Spirit, we become children of God. That means everyone who is in Christ becomes our brother and our sister. The person sitting next to you is not just a friend or an acquaintance. In Christ, that person is your brother or your sister. Please call the person next to you “my dear brother” or “my dear sister.” In Jesus, our relationships have been made new. Now, some people may not have a good relationship with their biological brothers or sisters. There may be conflict. There may be a disconnection. Some don’t even speak to each other. But even then, can you break that relationship completely? No. You are still family. In the same way, our spiritual relationship—formed by the blood of Jesus—cannot be broken. We share the same Father. We belong to the same family. We are brothers and sisters in Christ.

So our fellowship must be genuine. We need to be honest with one another. A fellowship that is built on falsehood cannot last—it can collapse at any moment. In our community, we are called to love one another, to understand one another, and to forgive one another. James 5:16 says, “Therefore confess your sins to each other and pray for each other so that you may be healed. The prayer of a righteous person is powerful and effective.” The apostle James tells believers to confess their sins to one another and to pray for one another. But honestly, it is not easy to confess our sins to others. We are afraid that people might judge us. It is hard to open up about our struggles and our wounds. Sometimes the problems we carry feel so heavy. Without courage, we cannot speak. We feel as if we share, we will be condemned. But it becomes possible through the work of the Holy Spirit. The Holy Spirit gives us courage. And when we confess our sins, the power of Jesus’ blood purifies us. We realize that we are all sinners. No one can say, “I am better than you,” or “You are the bigger sinner.” And that realization humbles us. It breaks down pride. It opens the door for true fellowship.

During the retreat, Buela, Jonathan, and Jeremy shared their testimonies with honest confessions of their sins. Jonathan’s struggle with sin was intense. We could feel how real the battle was. But the reason he fought against sin like that was that he deeply loved God. And as he shared, we didn’t just listen—we entered into his struggle. We shared in his pain. And when he spoke about God’s work in his life, we also shared in his victory. We rejoiced together. Jeremy is an accomplished young man—he graduated from UCLA and is now pursuing his DNP at Columbia. But through his testimony, we were able to see his inner struggles, his sense of inadequacy, and his pain. And we saw how he was changed as he encountered God’s unfailing love. Through these honest and sincere testimonies, something happened to all of us. We began to see our own sins more clearly. And we were led to repent. We were led to confess.

Last Friday, we had our post-Spring Retreat fellowship. More than ten young people shared their reflections, openly confessing their sins. That is not an easy thing to do. It takes courage. But the reason it was possible is that trust had been built among us. There was a sense of safety—a trust that even if I confess my sins, I will not be condemned. And as they listened to one another’s honest repentance, they began to realize, “I am the same. I am also a sinner.” And that gave them the courage to open up. And in that moment, the Holy Spirit was at work among us. This is true Christian fellowship. A fellowship that stands on the truth. A fellowship in Jesus. A fellowship where we trust one another and love one another.

So I want to encourage us to continue this true Christian fellowship. It would be great for each fellowship to have times of reflection sharing. What is the name of our church? It is University Bible Fellowship. Our church is a community that seeks the true Christian fellowship grounded in love and truth. I pray that we can continue to grow in true Christian fellowship. Amen.