Can a preacher really preach a whole book in one expositional sermon? If so, how?
Suppose your friend asks you to summarize a two-hour movie you just saw. You could do that in five minutes or less. You would summarize the movie’s contents, emphasize what the movie is about, and by pointing to key moments in the movie.
In the same way, a preacher can preach a whole book of the Bible in one sermon. He can summarize what it’s about. He can give an overview of its contents. He can point to key events and turning points. And he can highlight what is unique about that particular book compared with every other book in the Bible, just as one might with a movie. But—and this is different than retelling a movie—a preacher must also apply the spiritual weight of the entire book to the hearts of his hearers. “What’s the main thing John wants to impress on his hearers through his Gospel? How can I communicate that?” “What’s the main thing Paul wants to teach the churches of Galatia? How can I help my congregation to see that through the different parts of this letter?”
In order to preach a faithful expositional sermon the preacher doesn’t need to exhaust every detail in the text. Rather, he simply needs to explain and apply the main point of the passage, even if that will take a little more work than with a paragraph or verse.