Three Levels Movement, the Sanjiejiao (三階教) or Pufazong (普法宗) is a popular religious movement based on the teachings of the Chinese Chán monk teacher Xinxing (信行禪師)(540-594).
Xinxing taught in the stage of mofa buddhists must learnt every buddhism teachings (Pufa). He taught tapas, begging to meal, one meal daily, worship every lives as buddhas (based on the Tathagatagarbha doctrine), building endless saving houses, or Wujinzangyuan (無盡藏院) for giving to monks and people, and sky burial.
Base in Hua Du monastery (化度寺) in Chang'an, the movement was very popular in 600-700 AD. The monks live in the Sanjiejiao house, or Sanjieyuan (三階院) inside Buddhist monasteries and build endless treasure houses. Its practices faced heavy criticism from many Buddhists and restriction by buddhist Emperor Wen of Sui and Wu Zetian as unorthodox teachings. Emperor Xuanzong of Tang order the destruction of the Wujinzangyuan, the Sanjieyuan and the school texts, spare the endless savings. Bhikkhuni Zongjing (總靜) in the Zhixin monastery(直心寺) was a known practicer died in 831. Some texts, such as part of the three stages teachings (三階教法) was kept in Japan monasteries. Some were also found in Dunhuang texts and grottoes. 
- 開元釋教錄 (Taisho Tripitaka No. 2154)
- 三阶教研究论著目录A Summary of Materials and Studying Catalogs on Teaching of the Three Levels 作者:朱生云,王惠民, 敦煌学辑刊Journal of Dunhuang Studies 2008年第01期
- Charles Muller, East Asian Apocryphal Scriptures: Their Origin and Role in the Development of Sinitic Buddhism
- 矢吹慶輝 (Yabuki Keiki), 三階教の研究 (Sangaikyō no kenkyū) (Studies on the Teaching of the Three Stages). Tokyo: Iwanami shoten, 1927.
- 西本照真 (Nishimoto Teruma), 三階教の研究 (Sangaikyō no kenkyū). Tokyo: 春秋社(Shunjusha), 1998.
- Hubbard, Jamie, Absolute Delusion, Perfect Buddhahood: The Rise and Fall of a Chinese Heresy. University of Hawaii Press, 2001.
- Hubbard, Jamie, Mo Fa, The three Levels Movement and the Theory of the Three Periods, Journal of the International Association of Buddhist Studies 19 (1), 1-17, 1996