This is a long post, but a great illustration to help us understand 1 John.
John Piper, in a sermon, “The Strong Need Strength,”
Compare 1 John for a moment to a letter that a mother writes to her daughter who has gone away to college. The mother gets word that there has been an unusual outbreak of smallpox on the campus with five cases confirmed. Her daughter is not among the victims—at least not yet. The mother knows that, but goes to the card shop and gets a card that has a little rhyme on the front cover that says,
I ask not that God give you wealth,
But daily beg him for your health.
Then she writes on the back of the card,
Don’t misunderstand. I’m not writing you out of distress because I think you are among the victims of the smallpox outbreak. On the contrary I am rejoicing that you are well!
Of course, I don’t want you to get sick. Take the necessary precautions. But I write because my heart is full of memories and confidence. I recall how you once had measles and your face looked like a prize fighter in the 15th round—and how you got completely well!
I remember how you were so brave back when the small pox vaccinations were still given in our little town with a piece of broken glass. You took it without a tear, and now you’ve got that protection in your body.
You’ve been so strong and healthy! It seems, as I look back, that when everybody else was falling with the flu, you conquered the enemy and hardly got the sniffles. You obviously know some wonderful secret!
So hold on to what you’ve got. Take heart in the manifest work of God in your life. Keep yourself in his wonderful health.
I am full of joy in the gift of health we share.
Why did this mother buy this card and write this note? The card said, “I beg God daily for your health.” Then she wrote, “I don’t want you to get sick. Take the necessary precautions . . . Hold on to what you’ve got . . . Keep yourself in his wonderful health.” So it’s clear that at least part of her reason for writing is to help the daughter stay healthy.
But on the other hand, she said, “I am not writing you out of distress . . . I rejoice that you are well.” She spends most of the letter delighting with her daughter in how well she is and how she has been able to conquer sickness again and again.
What’s the relationship between these two strands in this letter? On the one hand, the mother wants to intensify her daughter’s appreciation for the gift of health, and strengthen her confidence that she will be able to withstand disease. And on the other hand, she wants her to hold on to the health she’s got and not do anything to lose it.
The relationship between these two strands is that the mother wants her daughter’s appreciation for the gift of health and her confidence in staying well to motivate her to be vigilant in keeping the health she has.
In other words, when the daughter sees the value of what she has, and feels the assurance that she really can be victorious over sickness, she will have the zeal she needs to hold fast to what she has instead of throwing it away on all-night parties and foolish eating and no exercise.
The Same Two Strands in John’s Letter
It seems to me that 1 John is built on this same pattern. If you look up all the places where John tells us why he is writing, you find two strands just like the pattern in this mother’s letter.
First, he says in 2:1, “I am writing this to you that you may not sin.” In other words, he doesn’t want them to get sick. He wants them to stay well. Then in 2:26 he says, “I write this to you about those who would deceive you.” In other words, he is warning them about some dangerous germs of error in the community. “Watch out for the germs! Don’t get sick!” That’s one strand in John’s letter, just like one strand in the mother’s letter was to urge her daughter to vigilance—don’t throw your health away on all-night parties and junk food and lazy habits.
But there is also a second strand in John’s letter. In 2:21 John says, “I write to you, not because you do not know the truth, but because you know it.” In other words, “I am not distressed because I think you have been infected by these germs of error. I don’t think you are among the victims of ‘smallpox’. In fact I am rejoicing in your good health.”
As our text (2:12–13) says, “I am writing to you, little children, because your sins are forgiven for his sake. I am writing to you fathers, because you know him who is from the beginning. I am writing to you, young men, because you have overcome the evil one.” Not because you are sick but because you are well—thank God!
This strand continues to the end of the letter in 5:13. John says, “I write this to you who believe in the name of the Son of God, that you may know that you have eternal life.” In other words he is writing to strengthen their assurance that they will indeed live forever. No sin will conquer them.
So what is John’s purpose in this letter? On the one hand he says, “I am writing to help you not to sin. I am writing to warn you against the deceivers.” And on the other hand he says, “I am writing because you are forgiven. You know the truth. You are strong. I want you to have assurance of eternal life.”
On the one hand he intensifies their appreciation of what they have in Christ, and deepens their assurance of eternal life. And on the other hand he warns them about those who would deceive them, and urges them to have a vigilance against sin.
And how do these two strands of John’s letter relate? I think John means for the strand of confidence to motivate the strand of vigilance. He wants to motivate the fight with the confidence of victory. The aim of our text (2:12–14) is to give the motivation needed to carry through on 2:1, “I write that you may not sin.”