This book was required reading from my therapist, who values it as very foundational. The premise is that--just as our physical selves are what we eat--our emotional selves are what we think. The first part of the book is about lies we shouldn't believe, and the second is about the truths we should. All of the information is presented within a Christian context.
I felt impatient with this book for the most part: not because I didn't agree with Thurman, but because I did. I just didn't find his words particularly insightful.
Then I stumbled upon a "truth" in the second part of the book with which I didn't automatically agree: specifically, that emotional pain is good. I learned a lot--especially about myself--upon delving into Thurman's thoughts on this. (Essentially, he draws the analogy of emotional pain : smoke alarm :: internal problem : fire. So emotional pain like quick anger, depression, anxiety, etc. is good because it warns us that there's a deeper problem to which we need to attend.)
Overall, I do think this book a good starting place within the realm of Christian counseling: just a good way to insure that all parties are on the same page before moving forward.