I just read a book that talks about the difference between believing in Christ and believing what Christ says. I've mentioned Suzette Haden Elgin who starts with "be ye therefore perfect" (and the "yes, I really mean it") as a starting place.
While I've bought copies of Steadfast and Immovable: Striving for Spiritual Maturity by Robert L. Millet for people in the past, I think I am going to start buying copies of this book for some people now. Guess that is how I evaluate books -- have I felt the need to buy copies of it for people I know?
This book passes the test. Even better, like everything else, it is available for free through interlibrary loan.