Changed into His Image is a good book, maybe even great book. This book helped me to better understand how Christians change, but more specifically how Christians change into the image of Christ. He covers topics such as recognizing the evil within, mortifying the flesh, searching for wisdom, being Word-filled, and many other great topics. He does a great job at giving vivid word pictures and illustrations to help grasp the book's concepts.
Jim Berg explains that Christians, no matter their circumstances, ought to be growing and changing into the image of Christ. He explains by saying,
"A sea captain who understands the basics of navigation and sailing knows how to make progress no matter what the direction of the winds or currents. In much the same way, if you understand these basics for biblical change (i.e., sanctification), you can experience growth in your life no matter what challenges confront you at the moment. Furthermore, you can effectively help others to change and grow as well."
I hope you read this book, but better yet, apply it's principles into your life.