The Way of the Celestial Masters is the founding movement of organised, communal Daoism, and it marks the moment the tradition became a church rather than a body of texts.
A revealed theocracy
The movement was founded in the second century by Zhang Daoling, who reported a revelation from the deified Laozi appointing him Celestial Master. It established a self-governing community in the Hanzhong region with its own clergy, liturgy, moral code and registers of gods, governing its adherents through a network of parishes and rites of confession, petition and offering. This is the apparatus of an organised religion, and its appearance is what distinguishes communal Daoism from the earlier philosophical texts.
A lineage that persists
The community submitted to the warlord Cao Cao in 215, which dispersed its members and spread its tradition across China. The title of Celestial Master became hereditary in the Zhang family, later seated at Mount Longhu, and the lineage has continued, with interruptions, into modern times. Its living continuation is the Zhengyi tradition of married, temple-and-community priests, so the priesthood that serves much of Chinese folk religion today traces its authority directly to this second-century foundation.