The first half of "Spiritual Rhythm" gives a detailed look at each "season" of the soul - winter, spring, summer, fall - and explains each one, including with them appropriate responses to each season. (For reference, a season, according to Buchanan, do not necessarily have anything to do with age but our spiritual state.) The second half of the book goes into more detail on behaviors and actions that are relevant to each season.
Honestly speaking, I loved this book. Buchanan writes in a way that's almost poetic yet easily understandable. The first half of the book was - undoubtedly - my favorite part. As I read, I found that I could most definitely relate to each season in some way or other, and I think he explains each one in a way that makes sense. He uses metaphors related to nature, but they weren't so over my head that I couldn't understand them. His practical applications (or "activities" as he refers to them) were grounded in spiritual and biblical truth and were relevant to the accompanying season.
What I probably loved the most about the book is that there was no point where he lost my attention. I was never bored while reading the book, and I never had to force myself to pick it up to continue my reading. With that being said, there were times that I needed to take a break from the book in to mull over the content, particularly the parts that I felt were the most relevant to me at the time. And I liked that Buchanan took me down that road and made me feel connected to what he had to say. He gets personal with the reader and invited me to get personal myself as I worked through each season.
The second half was definitely good - I just didn't connect to it in quite as deep a personal way as I did the first half. However, I think the second half was just as relevant as the first half. You can't really have one apart from the other - they go hand in hand.
All in all, I thought this book was a fantastic read, one that I would highly recommend. I have never read a book quite like this one. I felt that it was original and offered a new, fresh perspective into living the Christian life. It's insightful and relevant for everyone and a book that I have no doubt I will reference for years to come.