Fear comes when you are not living your core values (core beliefs). Most courageous people are very authentic and they live their core values. Who comes to your mind when you have to think about a courageous leader? There are many of course. For me, Mahatma Gandhi comes to my mind. All his strength he got by living his core values to the most. When you live your core values nothing can scare you and not even death. Read about any of the world top leaders and you will understand this very well. Nature has inserted a very beautiful mechanism with in us to tell us if we are living our values or not. When you comprise on your values your internal system will tell you and that why you will be unhappy when you are not living your values. When you are in sync with values you will be the happiest and courageous person.