Lesson 1.
Being Certain Jesus Is the Son of God

1 John 1:1-4

To become "contagious" Christians, we must be certain about the fundamentals of our faith, which include being certain Jesus is the Son of God. 1 John tells us how to be certain of our faith in an uncertain world. We face many uncertainties: the stock market, the economy, our health, retirement, etc. That's why we need this book. No book in the Bible is more needed today than 1 John because it is a book of certainties.

The author of this book doesn't identify himself. However, based on the writing style, there is no doubt it was written by the apostle John. He also wrote four other books in the New Testament. What are they?


John was the only disciple present at Jesus' crucifixion. When Jesus sees His mother and John standing near His cross, He asks John to take Mary as his own mother. Therefore, what do we read in John 19:27b?


Apparently, John took care of Mary, the mother of Jesus, until she died. No one was closer to Jesus than John. Because of his humility, John never mentions his own name in his gospel or his epistles; he simply calls himself the disciple, whom Jesus loved (Jn 20:2). So, John writes this epistle based on personal experiences.

Because of persecution, John moved from Jerusalem to Ephesus, where he wrote this letter around a.d. 85, more than fifty years after the crucifixion of Jesus. John was around age nineteen when he began to follow Jesus and is now in his seventies. All the other disciples have met violent deaths, so John is the only one still living. He is writing this letter to reassure Christians about their faith and to combat false teachings about Jesus. In this letter we find the word know or knoweth more than thirty times. How does John state the main purpose of this letter (1 John 5:13b?)


This is one of many things we must know for sure if we are to be "contagious" Christians. However, John begins this epistle by declaring the most important prerequisite for becoming "contagious" Christians—being certain Jesus is the Son of God. To have this certainty, there are three things we must know...

1. We must know Jesus has always been God

1 John 1:1a

Jesus was no newcomer when He stepped into history as a baby in Bethlehem. John writes: That which was from the beginning (1:1a). Before the beginning of creation, time, and history, Jesus existed. How does John make this even clearer in John 1:1?


Then, John writes: And the Word was made flesh, and dwelt among us (Jn 1:14a). In the beginning, Jesus already existed. Jesus did not begin to exist when He was born in Bethlehem because He has always been God. To be certain Jesus is the Son of God, not only must we know Jesus has always been God, but also...

2. We must know Jesus was God in human form

1 John 1:1b-2

These verses were written to combat the false teaching of the Gnostics, who taught that Jesus didn't have a real body of flesh and blood because God could not become a human being. Referring to Jesus' body, John writes: which we have heard, which we have seen with our eyes, which we have looked upon, and our hands have handled (1:1). John was an eyewitness to the fact Jesus had a body of flesh and blood because he had personally heard... seen... and even touched His body. Jesus wasn't a spirit or an illusion. John is saying, "I know what I'm talking about. I was there—I've heard Him, I've seen Him, and I've touched Him." To reveal beyond any doubt Jesus was God in flesh and blood, what words of Jesus does John record in John 10:30? (See also John 14:9b.)


In this first verse of his epistle John calls Jesus the Word of life (1 Jn 1:1b). John often calls Jesus the Word. As the Word, Jesus conveys, or communicates, God. You see, when Jesus is speaking, God is speaking.

If you were God, with the power to do anything, and you wanted to communicate with ants, what would you become? An ant! If you wanted to communicate with birds, what would you become? A bird! If you wanted to communicate with human beings, what would you become? A human being! That's what God did in Jesus Christ. Jesus is not only the Word of God; He is the Word of life. In John 6:63b, what does Jesus say about the words He speaks?


Jesus tells us He is the only way to eternal life. Jesus is not a word from God; He is the Word of God. John heard Jesus say, I am the way, the truth, and the life: no man cometh unto the Father, but by me (Jn 14:6). Therefore, he writes: (For the life was manifested, and we have seen it, and bear witness, and shew unto you that eternal life, which was with the Father, and was manifested unto us;) (1 Jn 1:2). This means eternal life resides in Jesus.

One day Lazarus, one of Jesus' close friends, dies (Jn 11). Lazarus is the brother of Mary and Martha. When word comes to Jesus that Lazarus has died, He travels to Bethany, the home of Lazarus, Mary, and Martha. As He arrives He is informed Lazarus has been buried in the grave four days (11:11-17). When Martha hears Jesus is coming, she runs out to meet Him and says, Lord, if thou hadst been here, my brother had not died. Jesus tells her, Thy brother shall rise again, to which Martha replies, I know that he shall rise again in the resurrection at the last day (11:20-24). It is as though Jesus says, "Did you say, resurrection at the last day (the end of time)? Martha, you don't understand the truth about Me." So, to clarify her understanding, what does Jesus say to her in John 11:25?


In others words, Jesus says, "Martha, the resurrection is not something for which you must wait; the resurrection is standing in front of you! I am the resurrection, and the life." Because Jesus is God, He is the origin of all life—literally, He is the life of all things.

To be certain Jesus is the Son of God, we must know Jesus has always been God, Jesus was God in human form, and...

3. We must know Jesus personally

1 John 1:3-4

John writes: That which we have seen and heard declare we unto you, that ye also may have fellowship with us: and truly our fellowship is with the Father, and with his Son Jesus Christ (1:3). The word translated fellowship (koinōnia, coin-oh-knee'-ah) means to share in common or have in partnership. John and the other original disciples had a personal, private fellowship with Jesus. John is writing so we can have that same fellowship with Him.

Fellowship with Jesus didn't end when He was crucified. We can have an even more intimate fellowship with Jesus than the original Twelve had. After Jesus was crucified, Thomas did not believe He was resurrected and said he would not believe unless he could put his fingers in the nail prints in Jesus' hands and put his hand into Jesus' spear-pierced side (Jn 20:25). When Thomas finally saw the resurrected Christ, He offered to let Thomas touch Him as he had demanded. Then, what does Jesus tell Thomas in John 20:29?


Some people think they would believe in Jesus if they could see a sign or miracle, but Jesus says we are more blessed if we believe without seeing. All the proof we need is in the Bible and in the testimonies of other believers. In the story of the rich man and Lazarus, the rich man wanted someone to return from the dead to convince his brothers to be saved (Lk 16:30). But what does father Abraham tell him in Luke 16:31?


In other words, if the Bible won't convince them, nothing will. Through faith, we can have fellowship with Christ, along with John and the apostles. This faith is not based on wishful thinking, some mystical "mumbo-jumbo," or even a second-hand report. It is based on the eyewitness accounts of John and other apostles who heard, saw, and even touched Jesus. Just as in Lazarus' day, if the Bible and the testimonies of other believers do not convince someone today that Jesus is God's Son, nothing—not even someone rising from the dead—will.

John concludes his introduction: And these things write we unto you, that your joy may be full (1 Jn 1:4). This joy is the result of having a harmonious relationship with Jesus Christ. Just before His crucifixion, Jesus tells His disciples to keep His commandments (Jn 15:10). Then, what does He tell them in John 15:11?


Jesus doesn't call us to a dull, boring existence. Instead, He offers us full, or complete, joy that cannot be found in the world. This joy will be a major factor in your "becoming a contagious Christian."

To be a "contagious" Christian, you must be certain Jesus is the Son of God by believing Jesus has always been God and Jesus was God in human form, and then you must know Jesus personally.