Our practice of shakubuku has the power to break through the fundamental ignorance inherent in our own lives and those of others. Only a diamond can polish a diamond. Similarly, only human beings can help other human beings bring forth the full brilliance of their potential. Sharing the Mystic Law with others is the key to leading a truly great life.

From The Wisdom for Creating Happiness and Peace, part 2, revised edition, pp. 259-260