The preface to the Han Classic of Hongyang in Mixed Yuan Religion says: "The protector of Hongyang is now taught by Sakyamuni Buddhism and thinks he is the founder of Hongyang. In the past, Qingyang was bright, and in the future, Baiyang. " Hongyang robbery theory is related to Sanyang theory. Hongyang believes that the ideal Bai Yang world came when the world was completely robbed, that is, the so-called "Hongyang was robbed and Bai Yang prospered". Qingyang, Baiyang and Sanyanghui, which can be seen everywhere in the Ming and Qing Dynasties, are all related to Hongyang's purpose. Its origin is related to the theory of one meeting, two meetings and three meetings in Maitreya Sutra, that is, one meeting (past), two meetings (present), Buddha palm teaching and three meetings (future). Replace the "three meetings" in Maitreya's sacred land with Qingyang, Hongyang and Baiyang, representing the past, present and future respectively. This folk belief has influenced many other folk religious organizations.