The basic practice for Nichiren's followers is the constant recitation of the Daimoku, "Na-mu-myo-ho-ren-ge-kyo"(which means that one puts his faith in the Lotus sutra).

　Besides reciting the Daimoku inside of their halls, Hokke-so, priests who observe the Lotus sutra, also proselytize amongst the people, convincing them to become followers of this sutra, and spread it outside of the temple. In addition, some of them undergo such austere practices as hiking on set courses through steep mountains and bathing in cold fresh water at waterfalls to increase their power when praying. During the Edo period (1603-1867), sub-denominations of the Hokke-shugen, practitioners who led an ascetic life using the Lotus sutra for prayers, developed in several Nichiren denominations.

　Reverend Nichikyu (1662-1727), the third abbot of shochuzan Onju-in temple, completed one thousand days of austerities during the Genroku period (1688-1704), and he established rules for one hundred days of harsh austerities (aragyo). He compiled the "The sacred book on the transmission of prayers" (Kito-soden-sho) and thereby became the founder of the Onju-in denomination.