The Kingdom and the Cross is a very short devotional booklet designed to get the everyday reader to think about spiritual things. Smith is very clear about his purpose, “this little guide is meant to help expand your understanding of these two concepts (Kingdom and the Cross).” He goes on to say that he “may not have the best explanation of them…I offer…ideas and images that have been helpful to me in my journey.”
Smith focuses briefly on various devotional thoughts centered on these two issues and then gives a “soul training” exercise to help focus on the idea presented. These could be anything from reflecting on the Pietà to watching The Lion, the Witch, and the Wardrobe. There is also a study guide for small group study in the back.
The Kingdom and the Cross is not heavy reading and if you like something that can help you to connect to God using alternative media, especially art and cinema, this is a good beginners tool for helping you. It certainly is something that you could use in a discipleship weekend or something of that nature for new believers.
If you are looking for something deeper and more engaging, then you might want to look somewhere else. The book is not a terrible book and it uses some media connections nicely, it is just not something you would probably consider a “must read” for the more experienced, mature Christian.
If someone were to give it to you, I would definitely say take a few hours to read it through, you may find something here or there, maybe an illustration or object lesson; otherwise I would not personally spend money on this book because I prefer books with more substance.