As you prepare your sermon, there are numerous defining moments. That is to say, pivotal decisions that will impact the essential nature of the sermon. The whole process is important, and every little detail of your preparation will build the character of the message. But the defining moments will fundamentally change the outcome of your process. Therefore, it is helpful to be especially aware of these key points in the process.
Here are seven defining moments in your sermon preparation:
1. The choosing of the passage. If we genuinely believe in expository preaching, then the choice of passage will always be a key moment in our preparation. Why? Because that passage will be the boss of the message. We cannot say whatever we want using any passage. Some preachers do. We must not. If it is a series from a book, then the moment will primarily be the selection of the series, although the length of the next section to be covered will also matter. If it is a one-off message, then the choice of the passage matters for the content of the sermon. And also the timing of that choice will matter for how much time we can give to the preparation. Some preachers make a good choice, but they make it so late that the preparation is adversely impacted by lack of time.
2. The decision to start preparing. If you have a tendency to procrastinate, and many of us do, then deciding to start preparing is important. If your routine is established and it works well, then this may not be a key point for you. However, if you find that life often presses in and the week is often eaten up before you even start the process, then this point is for you. Decide to start early. Just the first step. For me, that means pasting the passage into a document and starting to recognize the shape of the passage. Once you have started, even if only just, then the brain starts to collect and sort exegetical information, and the heart starts to bow to the truth of the text. Some helpfully choose to get started, even if only just, more than a week before preaching. Some even take some time to get started on every series, and even every passage, months before the time comes to preach.
In the next post we will continue the list of seven defining moments in the preparation of a sermon.
Biblical Preaching 
Even if preparing a given sermon is only going to take, say, six hours of my time (which is rare) I still find I need to spread that prep time across a week. I need the elapsed time for the ideas to progressively mature in my mind, for the threads to weave together, for the extraneous material to become apparent for pruning, and most of all for the narrative through-line to manifest.
It is so true that spacing out the prep is helpful. Actually, there are some benefits to a block of time, and some benefits to a broken up block of time . . . and the benefits are different!