Having faith is essential to the well-being of a person. Faith is believing without seeing and then acting on your belief. It's not enough to say you believe; you must put your faith into action. This means instead of just thinking you can get better, claim that you have been made whole. Show some faith!
Sometimes finding a faith to devote oneself to is a great self-help idea. During hard times we tend to dwell on what is troubling us and lose sight of the bigger picture. A religious faith helps one focus on that bigger picture while altering the focus from hardship to a higher power.
Do not forget that personal development means much more than just working on all of your skills. It also means working on who you are as a person. If you are religious, this can mean to work on your spirituality, and if you are not it means working on your inner peace.
In order to gain true personal development you have to make sure you take in and digest the bulk of the information you just learned. You not only want to make sure you remember everything you just learned but you want to also make sure you apply your new knowledge properly, only then can you see true personal development.