1 John 5:20

The Text

Three times in a few lines John says "we know," and here comes the last and largest of them: we know that the Son of God has come, and that he has given us something to understand with. Not just information, but a capacity, a faculty, a working mind for God. The point of that gift is relationship: that we know him who is true, and more than that, that we are in him who is true, by being in his Son Jesus Christ. And then the sentence lands with a thud that leaves no room for negotiation: this is the true God and eternal life.

The Core

Notice what John does not say. He does not say the Son came to give us rules, or a religious feeling, or a better version of ourselves. He says the Son came and gave understanding, and that this understanding terminates not in an idea but in a Person we are inside of. The Greek word behind "understanding," dianoia, means the thinking faculty itself, the mind as an instrument. Christ did not merely hand us facts about God; he repaired the organ by which God is known. That is why verse 19 can stand next to it so bluntly: the whole world lies in the power of the evil one, and the world's problem is not stupidity but blindness. Knowing God is not an achievement of the clever. It is a gift, and the gift has a name.

The Common Thread

John ends his letter with "keep yourselves from idols," and that is not a stray afterthought tacked onto verse 20. It is the conclusion. The whole Old Testament runs on this fault line: the living God who speaks and acts, over against images that have mouths and say nothing. Israel's prophets mocked the man who cuts a tree in half, cooks his dinner over one piece and bows to the other. The tragedy was never that idolaters were unsophisticated; it was that they gave themselves to something that could not give itself back. Now John says the Son has come and given understanding, so that we know the one who is true. Jeremiah's promise that God's people would one day simply know him, without needing to be taught, lands here, in a Person. The true God has stopped being an argument and become someone you can be inside of.

The Mirror

The uncomfortable move is that "true" in this verse is not mainly about accuracy. It is about reality, about what actually delivers. So the question John leaves you with is not whether you believe correct things but what you treat as real when the pressure comes. Watch where your mind goes at three in the morning: the mortgage, the scan result, your son who has stopped calling, the colleague who took credit for your work. Whatever you instinctively reach for as your security, your verdict on yourself, your source of life, that is what you are functionally calling the true God and eternal life. Most of our idols are not evil. They are good things asked to carry weight they were never built for: a career, a marriage, a body that still works, a reputation in church.

Today, open whatever you checked first this morning, the banking app, the work email, the scale, the group chat, and say out loud over it: "You are not the true God, and you are not eternal life." Then close it and leave it closed for the next ten minutes.

Context

This letter was written late in the first century, probably to a cluster of house churches around Ephesus, and something painful had just happened: people had walked out. Teachers who once broke bread with these believers had left and taken others with them, insisting they had a deeper knowledge of God, one that did not require taking the flesh and blood of Jesus too seriously. Those who stayed were left wondering whether they were the ignorant ones. Meanwhile Ephesus was a city saturated with shrines, processions, trade guilds that met under the patronage of a god. Refusing idols was not a private spiritual preference; it meant losing contracts, offending family, missing the dinner where the deals were made. "Keep yourselves from idols" cost money.

The Question

"This is the true God and eternal life" excludes a great deal, and it is worth admitting how that sounds. To the neighbour who prays sincerely to someone else, to the colleague who finds John's confidence insufferable, this reads as a claim to own reality. John will not soften it. But notice what he grounds it in: not our insight, not our moral record, not our tribe. He grounds it in a gift. We know because the Son came and gave us the ability to know. That removes the swagger without removing the claim. What it does not resolve is why the gift was given to these people and not to those, and John does not answer that. He simply reports that the whole world lies in the power of the evil one and that some have been pulled out. If that makes you uneasy, stay uneasy; the alternative is to pretend the rescue was our own idea.

The Profile

Picture someone in that congregation who has just watched a friend of twenty years leave for the other group, and who now reads a letter that keeps saying "we know, we know, we know." For them this was not triumphalism. It was someone handing them a floor to stand on. They had been told they lacked the deeper understanding; John says the understanding was given, and here it is, and it is not a secret. They heard "little children" from an old man who had likely held their babies at baptism. And when he finished by warning them off idols, they did not think of abstract priorities. They thought of the guild banquet next week, the small statue in the corner of their father's house, and the question of whether they would go.

Reflection

What did you reach for first this morning, and what were you asking it to give you?

Where does "the true God and eternal life" cost you something concrete this week, in money, in status, or in a relationship you would rather keep smooth?

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