John explicitly gives two reasons for writing his first letter. First, so that “joy may be complete” (1Jn. 1:4). There’s some question as to who’s joy is being talked about; whether it’s “our joy”, the joy of those proclaiming the good news and welcoming new believers into the family of God or, if it’s to complete “your joy”, that those who have believed might enter into their new life in Christ to the full. Either way, the joy, it would seem, is connected with the second reason John gives at the end of his letter:

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”

(1John 5:13 ESV)

At the core of joy in Christ is knowing we have eternal life. And such knowledge comes not from the memory of having made a profession of faith, but from seeing and recognizing all the evidences of faith. It’s what we know from what we’ve been taught and from what we can observe in our lives that gives us the confidence that we really are in Christ and sealed for eternity. Twenty times in this short letter John talks about what “we know” or about what “you know.”

For example, we know that we know Him because we keep His commandments (1Jn. 2:3). We know that, just as Christ is righteous, that those who seek to practice righteousness have been born of Him (2:29). We know that He appeared to take sins away (3:5) and we know that when He appears again we’ll be like Him (3:2). We know that we’ve passed from life to death because we love other believers (3:16). We know we abide in Him and He in us through the Spirit He has given us (4:13). There’s a whole lot, John says, that we know mentally, and we know experientially, that gives us the confidence that we really are who we say we are in Christ, sons and daughter of God. And all this so that we might know we have eternal life. And that, so our joy may be complete.

So, it’s not surprising that John would conclude his letter (1Jn. 5:18-20) with three more “we know’s”: 1) We know that everyone who has been born of God does not keep on sinning for Christ protects them; 2) We know that we are from God and not from the world which lies in the power of the evil one; 3) We know that the Son has come to give us understanding so that we can know “Him who is true” and abide in “Him who is true.” And He who is true is God’s Son Jesus Christ, the true God and eternal life.

And you think that would be it. That with such a declaration of what we know to be true of Christ, John would, as it were, drop the mic. That the music would crescendo as the words are left to echo in our hearts and minds, “He is the true God and eternal life!”

Yes and Amen! Hallelujah!

But John doesn’t stop there. He continues with six more words.

Six more words which we’re left to chew on. The necessary response to all we know. The required holy determination that’s to be ours in order to protect what we know. The warning that must be heeded if we are to continue to live in what we know so that our joy might be complete.

Little children, keep yourselves from idols. (1John 5:21 ESV)

Idols. Anything that supplants the supremacy of God in my life. Anything that so captures my regenerate heart that it supplants the One who regenerated it. Anything that competes for my allegiance to Christ. Anything that interrupts my abiding in Him. Anything I hold to for my identity other than who I am as an image-bearer of God and as a trophy of grace in Christ.

Little children, with everything you know, because of everything you know, keep yourselves from idols.

Search me, O God, and know my heart! (Psalm 139:23a ESV)

By Your grace. For Your glory.