Faith in Buddhism means establishing one's true self.

Buddhism Day by Day

Wisdom for Modern Life by Daisaku Ikeda
Tuesday, March 5, 2013:

 

Our individual lives are each infinite treasure houses. Our lives are clusters of blessings. Lasting happiness never comes from the outside. Everything of value emanates from within our own being. Faith in Buddhism means establishing one's true self. It is the recognition that the infinite horizon of the cosmos exists right here within the self. One's life opens out toward the cosmos and is enfolded in it; at the same time, one's life encompasses the entire cosmo.