Oi (well) - Ooi

...There are quite a few known examples of wells in the Middle Ages and Early Modern Periods where bamboo pipes or amulets were buried in wells when they were abandoned and rituals were performed. [Machida Akira] In the old days, water itself was important for life and production, and due to the influence of Taoism introduced from China, well water was considered to be sacred water, and shrines called Oi-sha and Mii-sha were enshrined in various places from ancient times. In addition, there were many wells that were mystical with special legends, such as Wakasa-i in front of the Nigatsu-do Hall of Todaiji Temple, and wells with Buddha statues placed nearby. The Ritsuryo state ordered stables to dig wells and make them available to passersby (Engishiki), and there are many old wells that are said to have been dug by Bodhisattva Gyoki or Kobo Daishi, but it is assumed that many of them were dug as part of social work by monks. ...

*Some of the terminology that mentions "Oi (well)" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…中近世の井戸では，廃棄時に竹管や護符を埋めこんで，祭祀を行った例が少なからず知られている。【町田 章】　古くは水そのものが生活や生産にとって重要であったことや，中国から伝来した道教の影響もあって，井戸水が霊水視され，古くから各地で大井社･御井社などとよばれる神社がまつられており，また東大寺二月堂前の若狭井のように特別な伝承をもって神秘化されたもの，また仏像などがそのそばに安置されたものなども多かった。律令国家は駅家（うまや）に井戸を掘らせて通行者に供することを命じているし(《延喜式》)，行基菩薩や弘法大師などによって開削されたと伝承される古い井戸は多いが，僧侶の社会事業の一つとして開削されたものが多かったことが推測される。…

※「大井（井戸）」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報