Kōshin

Kōshin (庚申) or Kōshin-shinkō (庚申信仰) is a folk faith in Japan with Taoist origins, influenced by Shinto, Buddhism and other local beliefs. A typical event related to the faith is called Kōshin-kō (庚申講), held on the Kōshin days that occur every 60 days in accordance with the Chinese sexagenary cycle.

On this day some believers stay awake to prevent Sanshi (三尸), entities believed to live inside the body of believers from leaving it during that night in order to report the good and specially the bad deeds of the believer to the god Ten-Tei.

It is not clearly certain when such custom arrived or came into fashion in Japan, although it is believed that by some time in the 9th century it had been already practiced at least by aristocrats. A Japanese monk called Ennin wrote is his travel book upon visiting Tang China in 838, that "Tonight people are not sleeping. It is the same as in our country on Kōshin nights." In the Muromachi period, Buddhist monks started to write about the Kōshin, which led to wider popularity of the faith among public. Numerous monuments or pillars called Kōshin-tō (庚申塔) (or also Kōshin-zuka (庚申塚)) were erected all over the country and the faith remained very popular through the Edo period. When the Meiji Government issued the Shinto and Buddhism Separation Order in 1872, folk beliefs were turned down as superstitious, Kōshin belief too losing popularity as a result.

Today, the Kōshin belief still survives, although it is far less popular and receives smaller recognition than it once did, due to the absence of any central organization to help promote such faith because of its folkloric nature. While many Kōshin-tō were moved, for example, to inside Buddhist temples or even to private houses to be protected, there are many remaining along historical roads as well. There are also well maintained Kōshin-dō (庚申堂), built in respect for the Kōshin, sometimes attached to Buddhist temples, or otherwise in stand-alone.

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Wikipedia