You can do anything you want because GOD is on your side. GOD has empowered us and given us a choice to be something extraordinary and because GOD is on your side, a little push from yourself can take you to great heights.
Here's a thing: I don't have any problems with any religions (I'm a Christian myself), but when a doctor starts going on about how we can better yourself and back it up by providing a story from a Bible, I have to put a stop to it. If it helps you, than fine. To me it does not belong in this book. To me the author is saying the power to change ourself is inside us, but than puts stories like these to tell you that you probably will need help from God.
Some of the advice is practical and makes sense (not caring about what others think of you, turning off negative thoughts, looking life on a positive note), but they are very hard to pull off. If you see somebody who does something you disapprove of, you will automatically judge them for it. The book says it is a reflection of ourselves, but you can't stop but judge that person for doing a negative action, even if you are guilty of doing it.
Another point is to not care what others think. This is true for a confident person because they don't seek acceptance, making them attractive to the opposite sex. However, me, an introvert, will not be able to turn that off just because I am told to do it. It is ingrained in me and will not be easy to change it. It takes years of practice and fine tuning to be this self confident person.
I think this book would have been useful when I was a kid and my brain was starting to change based on my environment and upbringing, but now it takes a big effort to become something you never even thought of changing until some obstacle was put in your way that is telling you to change or it won't move out of your way. I just don't think the book is practical for me as an adult because I have way too many things to juggle in order to keep moving forward. I need less things to think about, not more.