Post Series on 1 John 5:13-17:
- How Confident are You That You Have Eternal Life? (1 John 5:13)
- Confidence in Our Eternal Life Results in Prayer (1 John 5:14-15)
- Praying for the Prodigal Brother (1 John 5:16-17)
Finally, almost at the very end of his letter, John gives the primary motivation behind what he has written:
I write these things to you who believe in the name of the Son of God that you may know that you have eternal life. (1 John 5:13)
Everything John has written in 1 John–the commands to love, the demand for right doctrine concerning Jesus’ being the Christ, the Son of God, and even the insistence that true believers cannot even sin–has been written to teach those of us who believe in the name of the Son of God that we indeed have eternal life. Although much could be written about this profound statement, I want to focus on three aspects of it.
First, John makes it clear that his letter is written for believers. It is “you who believe in the name of the Son of God” whom John considers his true audience. John’s Letter assumes a prior knowledge of Jesus in order to confirm it, encourage it, and (where necessary) correct it.
Of course, this doesn’t mean that John has no concern for evangelism; quite the opposite. But it was the Gospel of John, not the First Letter of John, that was written to communicate the gospel to unbelievers:
 Now Jesus did many other signs in the presence of the disciples, which are not written in this book;  but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name. (John 20:30-31)
John’s Gospel was written to introduce us to Jesus; John’s Letter was written to confirm and perfect our standing in him–provided that we have in fact believed his initial statement about Jesus’ being the Christ, the Son of God.
Second, John’s Letter was written for believers in the name of the Son of God. John has no interest in a vague, anything-goes kind of faith. In the previous verse, John had just written that “Whoever has the Son has life; whoever does not have the Son of God does not have life” (1 John 5:12). Only in the Son do we find life. And only in his Name do we find salvation, for his Name represents his reputation, his character, and his deeds. The “Name of the Son of God” represents the gospel message that the Son of God went to the cross for us, and for our salvation.
One reason I love 1 John so much is that the gospel of Jesus is held high through John’s entire letter. Everything he writes points us to Jesus, whose own blood was shed to cleanse us from our sins. The Son of God actually became the sacrificial appeasement for God’s wrath against us. God himself drank the cup of God’s justice, and in so doing gave up his own life so that we might live. This doctrine is not just something that crusty, uptight, dry theologians insist upon; this is a message that embodies all of our hope and confidence in Christ Jesus, the Son of God.
Third, John’s Letter was written for believers in the name of the Son of God to know that they have eternal life. All through this letter, John has written several statements that very possibly might cause us to doubt our salvation. “Whoever makes a practice of sinning is of the devil, for the devil has been sinning from the beginning” (1 John 3:8). “But if anyone has the world’s goods and sees his brother in need, yet closes his heart against him, how does God’s love abide in him?” (1 John 3:17). “If anyone says, ‘I love God,’ and hates his brother, he is a liar; for he who does not love his brother whom he has seen cannot love God whom he has not seen” (1 John 4:20).
I struggle with these all the time! Am I actually “of the devil”?
But John’s purpose all along has not been to make those of us who believe in the Name of the Son of God doubt our salvation, but quite the opposite–he wants to assure us of our eternal life! In the face of the antichrists who preach a different gospel (not that there is a different gospel), John wants to assure us that we are on the right path if we claim Jesus as the Christ, the Son of God, through faith.
So I want to close this post with a note of pastoral comfort. If you are someone who struggles with assurance, who cannot seem to get your feelings in line with your theology that Jesus does love you, then this verse, along with the previous verse, are for you:
 Whoever has the Son has life; whoever does not have the Son of God does not have life.  I write these things to you who believe in the name of the Son of God that you may know that you have eternal life. (1 John 5:12-13)
Meditate upon these verses–claim them. Believe the promises, that if you have the Son of God, you have life–eternal life! Satan wants you to circle endlessly around your doubts, because in your doubts he can remove your eyes from Jesus and place them upon yourself.
You will never be worthy of the salvation that Jesus offers, so abandon any hope of finding such worthiness in yourself. But Jesus is worthy, and he freely offers you his own worthiness. To have Jesus is to have eternal life.