Most preachers (and I include myself in his) hate being asked for a throughline (or “sermon proposition”). That’s partly because it’s hard work to produce one. But it’s mainly because it usually exposes the lack of one, forcing more work on the sermon in order to create a credible and compelling throughline. But it always results in a better sermon.

One of the best preaching books I’ve read in the last decade is Denis Prutow’s So Pastor, What’s Your Point? If someone like Tim Keller or Don Carson had written it, it would be a bestseller. Prutow’s basic point is that most sermons don’t have a point. They may have points, but they don’t have a point. They have hundreds of sentences, but they can’t be summed up in one sentence.

The world of drama and storytelling calls this a “throughline,” the connecting theme that ties together each part of a narrative or speech. TED Head Chris Anderson says “Every talk should have one.” In TED Talks: The Official TED Guide to Public Speaking, he says:

Since your goal is to construct something wondrous inside your listeners’ minds, you can think of the throughline as a strong cord or rope, onto which you will attach all the elements that are part of the idea you’re building.

A talk can cover more than one topic and have more than one point, but all the topics and all the points must connect. If you think of your talk as a journey, the throughline is what connects all the major stopping points. Here’s how Anderson puts it:

A good exercise is to try to encapsulate your throughline in no more than fifteen words. And those fifteen words need to provide robust content. It’s not enough to think of your goal as, “I want to inspire the audience” or “I want to win support for my work.” It has to be more focused than that. What is the precise idea you want to build inside your listeners? What is their takeaway?

Most preachers (and I include myself in his) hate being asked for a throughline (or “sermon proposition”). That’s partly because it’s hard work to produce one. But it’s mainly because it usually exposes the lack of one, forcing more work on the sermon in order to create a credible and compelling throughline. But it always results in a better sermon.

A “throughline” should be as comprehensive as possible (incorporating each point of the sermon), as clear as possible (a simple rather than a complex sentence), as brief as possible (max of 15 words is about right), as memorable as possible (so that someone can take it away with them), as interesting as possible (intriguing rather than boring), and as unique as possible (so that it could only fit that text and no other).

If you can’t produce a throughline for your sermon. You don’t have a sermon.

David Murray is Professor of Old Testament & Practical Theology at Puritan Reformed Theological Seminary. This article first appeared on his blog, Head Heart Hand, and is used with permission.