That You May Know (1 John)

  • Matthew Jensen
  • 14 January 2019

Do you ever feel as if the passing of time and the worries of the world have eaten away at the confidence you first had as a new Christian? Do you ever doubt that you have eternal life?

If you do, you’re not alone. The readers of 1 John experienced this same doubt. They had heard the gospel of Jesus and believed he was the Christ, the Son of God; but, like us, they lived in a world that ate away at their confidence. In their case, it was worldly desires and false teachers that threatened their faith. What is it that’s eating away at yours?

John’s readers wanted assurance, so he writes to remind them of what Jesus’ death and resurrection have achieved, who they are as a result, and why they need not fear. May you find the same certainty after studying this letter, written “that you may know that you have eternal life” (1 John 5:13).

Table of contents:

  1. Our fellowship and sin (1 John 1:1-2:2)
  2. Assurance and love (1 John 2:3-14)
  3. The world and the antichrists (1 John 2:15-27)
  4. Being a child of God (1 John 2:28-3:12)
  5. No surprises and no deception (1 John 3:13-4:6)
  6. Love! (1 John 4:7-21)
  7. Victory over the world (1 John 5:1-12)
  8. Certain knowledge (1 John 5:13-21)
  9. For the leader

Before you begin

John wrote the letter we call 1 John so that his readers could be assured of their eternal 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 5:13)

His readers had already received eternal life by hearing the gospel of Jesus and believing that he was the Christ, the Son of God. This was the aim of John’s Gospel:

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)

So the recipients of 1 John knew the gospel message of Jesus and believed he was the Son of God, but they were struggling with uncertainty. Like us, they lived in a world that ate away at their assurance. They were worried about the new life they had, and didn’t know how they could be sure that it was eternal. As we read through 1 John, we start to see the two main causes of their concern.

First, this world is full of transitory desires that are not from God (1 John 2:16-17). Just living in this world with its attractions can cause us to question our faith. We know the things of this world will pass away, yet we can spend so much time chasing them that they become our source of comfort and assurance. Or maybe we are good at giving them up, but then we’re filled with doubt because we see others in the world who seem to be getting ahead by chasing the very things we have given up. Either way, the transitory desires of the world can make us lose focus on Jesus and strip us of our assurance.

Second, this world contains false teachers, who deny the truth that Jesus is the Christ, the Son of God (1 John 2:22-23). John explains that in order to spread their denial of Jesus’ identity to others (2:19), these false teachers have left the community they were once part of. This calls into question their previous confession that Jesus is the Christ, and naturally erodes the confidence of those in the community they abandoned.

In the face of these threats to assurance, John points to the believers’ new status as children of God (2:28-3:2) as a result of the death and resurrection of Jesus. This imagery of being a child of God is found throughout 1 John. It is the answer to the false teachers (note how it directly follows their description in 2:18-27), and it is also the answer to the world, because being born of God means that we have overcome the world (5:4-5).

I hope and pray that at the end of these studies, you will be certain of your own eternal life when you believe that Jesus is the Christ. By his death and resurrection, Jesus has brought us forgiveness for sin and made us children of God, and so established our fellowship with him, with the Father and with each other. Even though we live in a world that rejects Jesus, a world that follows the desires of the flesh and takes pride in possessions, we can be confident of our salvation. We have been reborn as God’s children, who wait for Jesus’ return and in the meantime are marked by love.

—Matthew Jensen, November 2018