1. Preach a shorter section – instead of feeling obligated to preach a whole book every time, why not preach a contained unit from a book for a series. You don’t have to give equal coverage to the whole book in this particular series, you can always come back for another section another time.
2. Have a Gospel/book of the year – we had a season in our church (over a year) where we were in Mark’s Gospel, but we didn’t want to be preaching it for months on end. We planned so that we had the Easter section at the right time of the year, but in the months before that we had covered some sections in midweek groups instead of on Sundays. This meant that our shorter series on Sundays were more focused and could be “branded” separately to allow for renewed energy in each mini-series. We also had breaks from Mark to spend time in other types of series and other types of biblical literature.
3. Preach a landmark tour – this is a way to preach a book without giving every verse equal attention. You can preach the landmarks of a Bible book over the course of a few Sundays. For example, you might preach Romans by starting in 1:16-17 to launch, and then touching down in other keys texts like 3:21-25; 5:1-8; 8:1; 12:1-2, etc. Obviously, you will need to give some overview of the flow for this approach to work, but it allows you to zero in on the golden passages. If done well then the church will be motivated to read the whole book. You can also supplement with midweek discussions that cover more ground, although that is only one approach to take.
4. Preach different sized chunks – this is similar to number 3, but is more intentional about covering the whole book. You could launch a Romans series with 1:1-17, but then cover greater ground with a couple of the messages in a series covering several chapters. For instance, you might have a message covering 1:18-3:20, then maybe one covering 3:21-5:21, etc. You could preach an 8-week series with three or four of the messages covering three chapters and then the other four focusing in a bit more – i.e. chapter 8 on its own, or chapter 12.
Have you found other ways to run shorter series on longer books?