San-jie-jiao (Religion of the Three Stages) was founded by Xin-xing during the Sui Dyanasty, and reached its peak in the Tang Dynasty. It flourished about three hundred years and attracted quite a lot followers. Since the Eastern Jin Dynasty, there were always wars appeared in the various parts of China,therefore, people suffered a lot because of these envirement. Xin-xing declared the Wu-jin-zang-xing (Limitless Activities) to encourage his followers. It attacted lots of common people to attend, and also lots of wealth was donated to its temples. Xin-xing wrote the San-Jie-Fo-Fa (Dharma Teachings of the Three Stages) during his early dharma preaching career. He quoted from many Buddhist scriptures to prove his ideas. He wanted this work to become the textbook for his followers. This thesis is a textual analysis of this important work. Through this study, we hope we can understand more about his unique ideas,and know more about why this religion was condamned and forbidden by the government in the later Tang Dynasty.