There is little dispute in the Church over the claim that the Apostle John wrote the following N.T. books: The Gospel of John, the epistles of 1, 2, and 3 John, and Revelation. As we shall see, the Gospel of John is a lengthy gospel booklet; the first epistle of John was written to give assurance of salvation; the second epistle was a personal letter written to “the chosen lady and her children”; the third epistle was written as a personal letter to encourage “the beloved Gaius”; and the book of Revelation was a message from Jesus that was sent to various churches.

To understand a book in the Bible, it is important to understand the author’s purpose. Why did the author write? What did he hope to accomplish? John told us why he wrote his Gospel in John 20:30-31:

“Therefore, many other signs Jesus also performed in the presence of the disciples, which are not written in this book; but these have been written so that you may believe that Jesus is the Christ, the Son of God; and that believing you may have life in His name.”

The epistle of 1 John is an important follow-up to the Gospel. John wrote in 1 John 5:13:

“These things I have written to you who believe in the name of the Son of God, so that you may know that you have eternal life.”

John is saying to those who have believed in Jesus that they can know—right now, in this life, and before they die—that they have eternal life or salvation in Christ.

My purpose in this article is to examine John 20:30-31. John made it clear in verse 30 that Jesus did many things, but he was selective in what he wrote, given the goal he had in mind. In John 21:25, John said, with a bit hyperbole:

“And there are also many other things which Jesus did, which, if they were written in detail, I suppose that even the world itself would not contain the books that would be written.”

Let us turn our attention to verse 31. This time, I want to use a more literal translation:

“These things have been written so that you may believe that the Christ, the Son of God, is Jesus; and that believing you may have life in His name.”

The verse has two purpose clauses introduced by the Greek word hina and translated as “so that” and “that.” “These things” refers to all that John had written. The verb “written” conveys the meaning: “These things have been written and stand written.” John is saying that the things he wrote are undeniable facts.

The first purpose is “so that you may believe.” The verb conveys the meaning: “believe and continue to believe.” The second purpose is “that [by or through] believing, you may have life in His name.” The verb “have” points to a present and future possession. “Life” is eternal life, or salvation in Christ. Eternal life is received through faith in Jesus alone and never apart from Jesus (cf. John 3:16; Acts 4:12). Those who are saved in Christ know that they have eternal life as a present possession and as an eternal one.

Why did I change the translation to “the Christ, the Son of God, is Jesus”? You may know that the verb “to be” takes the same case after it as before it. In Greek, how do you tell which is the subject and which is the predicate of the verb? The subject will have the definite article “the.” In John’s statement, the two definite articles are with “the Christ” and “the Son of God.” Another example of this is in John 1:1: “the Word was God.”

What was John’s point? John wants the reader, whether Jew or Gentile, to understand and believe that the Christ (the promised Messiah), the Son of God, is the man Jesus from Nazareth—the man who was crucified and who rose from the dead on the third day. This may sound very straightforward to us today, but for the ancient Jewish and Gentile readers, this would have been very, very challenging.

The Jews rejected Jesus’ claim to be the Christ, the Son of God. Their leaders charged Him with blasphemy and crucified Him (Matt. 26:63–66; John 19:7). Then they tried to do everything in their power to destroy the claim that Jesus rose from the dead (Matt. 28:11–15). The Gentiles rejected any teaching that said a god could come to this earth as a real flesh-and-blood human being. They believed their gods could appear on earth, but only as phantom beings. For both Jews and Gentiles, a crucified god was the ultimate contradiction. Belief in a god who experienced the utterly vile death of crucifixion was unheard of. It was the epitome of folly and madness.

What are some of the points that can be drawn from what John wrote?

1. Jesus is a man, a real historical person who grew up in Nazareth over 2,000 years ago and worked as a carpenter (Mark 6:3). John wrote, “the Word (Jesus) became flesh and dwelt among us” (John 1:14). Note John’s choice of the word “flesh.” The ancient reader would not have missed John’s emphasis that Jesus was a real, flesh-and-blood human being.
2. Jesus is the Christ, the Messiah God promised to send to the nation of Israel. The angel said to the shepherds that the baby born in Bethlehem is Christ the Lord (Luke 2:11).
3. Jesus is the Son of God. The angel Gabriel said He “will be called the Son of the Most High” (Luke 1:32), and “the Son of God” (vs.35).

Peter, speaking by revelation, said, “You are the Christ, the Son of the God, the living One” (Matt. 16:16). Note carefully the definite articles “the.” The high priest asked Jesus, “Are you the Christ, the Son of the God?” and Jesus answered, “Yes” (Matt. 26:63–64).

1. God has a Son. The salvation of sinners is found only in God’s Son, Jesus. John confirmed this truth in John 17:3: “This is eternal life (salvation), that they may know You, the only true God, and Jesus Christ whom You have sent.”

In Acts 4, the Jewish religious leaders tried to stop Peter and John from preaching about Jesus and His resurrection. But Peter boldly declared:
“There is salvation in no one else, for there is no other name under heaven that has been given among men by which we must be saved” (v.12).
Note the verb “must.” It reinforces the truth that it is God’s design that salvation (eternal life) is found in no one else but Jesus.

1. If you reject the truth that God has a Son, you can never be saved. This Son is called “the only begotten Son” (John 3:16)—that is, He is the unique, one-of-a-kind Son. Furthermore, this Son is God. John 1:1 says, “The Word (Jesus) is God.” Verse 18 says concerning Jesus: “the only begotten God who is in the bosom of the Father.”
2. If you are open to the idea that God has a Son, but you reject the teaching that Jesus is that Son, you can never be saved.
   1 John 4:15 says: “Whoever confesses that Jesus is the Son of God, God abides in him, and he in God.”

1. If you reject the truth that Jesus, the Son of God, is fully God, you can never be saved.
   Jesus said to the Jews: “Unless you believe that I AM, you will die in your sins” (John 8:24).

Do you believe the truth that the Christ, the Son of the God, is Jesus?
In other words, do you have eternal life in Christ?
This is the only fact in your life that will matter for all eternity.