A promise is a very unique kind of thing, especially when God is in the business of making one. I might make all kinds of promises. And sadly, I often break my promises because I’m incapable of doing what I say; or because I’m ultimately unwilling to keep my word. But when God – the unchanging and all-powerful creator of all things – makes a promise, we encounter something rather different. People make promises they can’t keep all the time. But when God makes promises, he is incapable of not keeping them.

A promise is a statement about the future, and when God makes promises, they differ from all other such statements. We talk about possibilities sometimes. It’s possible that I could get this dream job I’ve been looking for. It’s possible that I could convince this wonderful woman to marry me. It’s possible that I might take a trip to Europe next year. Possibility is tantalizing at first. But it is the language of uncertainty: it might happen, or it might not. And in human life, that’s half the thrill. The possibility that something might not happen is motivating and energizing. It’s encouragement to try hard to carry out what’s possible. What’s possible is much better than what’s impossible, of course.

Promises – when God speaks – are also different from imperative statements. You should do this. You should do all kinds of things. But the question hiding in these statements is obvious: I’m supposed to do this, that, or the other thing. But will I? The imperative is the language of the law – the demand that we do, or do not, do something. But the law leaves us with an unanswerable question: will I do as God commands? If we can really hear what the law says, the answer is usually no. Only the self-righteous among us think the answer is maybe. And if you think the answer is yes, then you haven’t even begun to see what sin and death really are.

And this, of course, leaves us in a terrible conundrum. If we’re left with only imperatives and possibilities when it comes to God, then we are in the driver’s seat of what happens in the end. Salvation is on the line, and I’m the only one who can determine the outcome – if everything goes according to plan. I’m not all-powerful like God, so maybe it won’t. This isn’t a reassuring place to be.

This is troubling not because of what I might eat for breakfast tomorrow. This isn’t even troubling because of who I might marry. Imperatives and possibilities are frightening when it comes to salvation because the outcome lies with us. And if I bank on myself, the outcome is an open question. I can only hope that I choose the right thing. The outcome of my salvation resides with me, not God, if this is true. When we’re talking about salvation, this difference between promises and possibilities – between law and gospel – becomes incredibly crucial.

When John writes his letters, he has a series of questions he wants to set straight. One of them concerns false teachers, which were common from the very beginning of church history. John says that he writes “these things to you about those who are trying to deceive you” (2:26). Paul’s letters say much the same thing: false teachers are everywhere, and we should be on guard against them.

Because the promise of God is sure and certain, you don’t need to seek after new and enticing teaching.

John wants to reaffirm his readers in the teaching of the gospel they had already received and give them guidance about how to deal with those who only pretend to preach the gospel. He wants them to rest in the teaching they’ve already heard. We don’t know much about those teachers John warns against, but that doesn’t matter much because we should always be wary of false teachers. And because John also wants to deliver assurance, what he writes is timely and timeless. It’s written there for us, just as much as the original recipients of his letters.

John comes right out and tells us what he’s sure about: “this is the promise he made to us – eternal life” (2:25). God is the promiser and the content of the promise is everlasting life. God promises everything to the sinners to whom he speaks. While John wants to help us discern false teaching, he doesn’t want to make us anxious or paranoid. God has made a promise that he intends to keep, and that promise is eternal life with Christ. We must indeed test the spirits (4:1), but this doesn’t negate the fact that “the anointing that you have received from him abides in you” (2:27). Indeed, the promise God makes to you can’t fail. It’s trustworthy by its very definition.

And because the promise of God is sure and certain, you don’t need to seek after new and enticing teaching. Hang on to the promise God has already made. After all, God can’t lie – he can’t go back on a promise. The teaching you have is everything you need: the hope of eternal life. Christ on the cross, forgiving your sin, is the only thing that now determines your future. Neither possibility nor imperative can change what Christ has already done for you. The task, for now, is to take your rest in this unbreakable promise of God instead of seeking new possibilities elsewhere.