The concept of the Three Eras was part of the Bửu Sơn Kỳ Hương tradition, which was revitalized by Tây An since 1849. The Lower Era was believed to be nearing its end in order to be replaced by yet another High Era.
Buddha Master Tây An claimed to be a messenger who had come into the world to warn mankind of the imminence of apocalypse. Those who heeded his words should take refuge in the Seven Mountains, or Thất Sơn. If they did so, they would be spared, while the wicked of the world would all perish in the coming cataclysm. The Seven Mountains were the place where Buddha Maytreya would descend after the world had been purified and where he would convene a Dragon-Flower Assembly, where those who had survived the apocalypse would gather. Maytreya would sit on a lotus throne. Thus would begin a new High Era, or Thượng Ngươn. Hue Tam Ho Tai, 1983, p.29. This millennial message made a religious believer and violent rebel just different phases of the same salvation process.
It should be pointed out that the social work arguably appealed to members of sectarian groups. Non-orthodox movements in traditional China and Vietnam arranged financial aid to poor peasants, established asylums for the poor. The sectarians also collected money for the funeral rites to help those households, which could not afford a proper funeral. Some sects prohibited gambling, other forbade alcohol, tobacco and opium. Most non-orthodox sectarians believed themselves to be living in the second kalpa, and they anticipated the arrival of the third and the last era.
Known in China since the 6th century AD, non-orthodox groups held vegetarian feasts and practiced a doctrine of "Three world stages," which was arguably inspired by Maythreya-theme. According to this doctrine, the forces of Light will triumph and be manifested on earth in the person of Ming-wang, or Minh Vương. This Maytreya-oriented millenarism provided its adepts with a picture of the Golden Age, revitalized after the predicted cataclysm. According to the authorities, these practices were considered as self-styled and therefore were illigal.
Sectaries claimed that there would be only Three Kalpas, each "governed" by the Buddha sent by the Eternal Mother. At the end of each period those who had been saved would be greeted by a Dragon Flower Assembly, or Hội Long Hoa. The assembly was to be held in the Eternal Mother's palace.
The term Long Hoa was taken from the name of the bodhi tree of Maytreya whose flowers were said to resemble dragons' heads. The turning of the kalpa meant the elimination of existing society and the coming to power the followers of the Eternal Mother.
The sectarians believed that Buddha Dipankara presided at the first Dragon Flower Assembly, or Lung-hoa hui. Since Maytreya-oriented millenarism implied revitalization of the Golden Age, i.e. radical social change, the political implications of the belief in the advent of Maytreya were obvious.
Like other Buddhists, followers of Hòa Hảo Buddhism believe Nirvana is the ultimate destination of their religious life, the liberation from sufferings. Aside from this basic Buddhist belief, Hòa Hảo adherents also believe that liberation and salvation can only be achieved via a certain selection process, also known as the Long Hoa Assembly.
In Chinese and Vietnamese Buddhism, it became usual to distinguish three periods. First, 500 years during which the Buddhist Law was correctly practiced. Then 1,000 years of counterfeit Law, followed by a final period of 1,000 years in which the Law just decays. The final period was known in Vietnam as the Mạt Pháp era. In short, there was a strong conviction that after each period some crisis would arise and some decisive change would take place.
According to the Bửu Sơn Kỳ Hương tradition and Hòa Hảo Buddhism, each of Three Eras was divided into three consecutive periods, higher, middle and lower. Each of these periods signified a specific condition of human beings. However, a general trend was believed to be a steady decline, from higher towards lower periods.
In Vietnam, the Bửu Sơn Kỳ Hương movement was not the only religious group to adapt the doctrine of Three Eras. Caodaism, and some other religious movements in Vietnam, shared the concepts of Three Eras and Long Hoa Assembly.
It has been understood that the Bửu Sơn Kỳ Hương tradition and Hòa Hảo Buddhism relied on the concepts of Three Eras and Long Hoa Assembly in order to emphasize Buddhist cosmology and anthropology by apocalyptic warnings and subsequently through the intense psychological reaction among the masses of adepts. Delivering his urgent message that “The Lower Era was coming to an end, and the Dragon Flower Assembly was about to be opened,” Hai Ngươn đã hết rồi... Lập rồi cái Hội Long Hoa - cf. Huỳnh Giáo Chủ. Sấm giảng thi thơ toàn bộ. Gíao Hội Phật Giáo Hòa Hảo, 1965. Santa Fe Spring, CA: Văn Phòng Phật Giáo Hòa Hảo Hải Ngoại, 1982, pp. 25, 71. . Huỳnh Phú Sổ wanted to engage the emotionally rural cultivators of the Hậu Giang area so as to gain and sustain their mass allegiance.