Here is an excerpt from Great Grandmaster Tae Yun Kim‘s book, The Silent Master:
Use Your Will to Conquer Fears and Weaknesses
Although some kind of shock is often a common way to rouse will power, it is not the only way. Sometimes you can summon your will simply from an intense desire to overcome stagnant, limited, or stifling circumstances. In this case, you have to be willing to let go of the past, and let go of your fears and weaknesses. These things have to go because they have kept you from moving in a positive direction.
Make the first rule of mental conduct a constant way of life: Identify your fears and weaknesses and conquer them.