Again, without Great Faith you cannot make the Great Vow. Without Great Vow, how can you practice with your whole being? And if you cannot do that, Great Determination cannot possibly arise. Therefore these four conditions must come into being in the proper sequence.
Faith is the foundation for anything we set out to do. Without faith we can’t accomplish anything significant. The Great Faith of Ch’an has three aspects: faith in yourself, faith in the method discovered and transmitted by Sakyamuni Buddha and faith in your Shih-fu, who is your direct connection to the Buddha Dharma. What is faith in oneself? It means believing that you can practice effectively, believing that persistence will lead to enlightenment. It means believing that you can, like Sakyamuni, eventually become a Buddha. If you lack this faith, if you think that enlightenment can only happen to others, your practice will falter. So faith in yourself is very basic.
How does this faith arise? At first it is hard to believe that you can be enlightened. However, if you are willing to try it, when you start to practice, you find your mind getting calm and settled. You may later get some other benefits, or even experience things not possible in ordinary life. You begin to believe: “Yes, I too can practice, I too can become enlightened.” Another way of generating faith is to acquire a good understanding of Buddha Dharma, of the principles of Ch’an, and to believe that these principles are true. You come to accept the idea that one can practice and get enlightened. You have never experienced it yourself, but you have an unconditional belief in it.
Great Faith, like the other conditions, is deeply related to what I describe as going from a “small” sense of self to a “large” sense of self and finally to a state of “no-self.” Great Faith starts with faith in oneself-you first have to affirm the very narrow sense of self. After all, who is it that must have faith? It is “I” who must have faith. So you must start with grasping the narrow sense of self. You must know this self in a very clear and solid manner and be confident that you can practice. This grasping of one’s “small self” is the basis of the power of faith.
— Getting The Buddha Mind by Master Sheng-Yen (page 18-19)