Ōharae-shiki
The 2=大祓式 is one of the Shinto purification rituals known as harae and is sometimes translated as "Great Purification". It is also known as the 2=中臣の祓. The Ōharae no Kotoba prayer is recited during the ritual.
The ritual is performed biannually on June 30 and December 30 at several shrines, but also as necessary, such as after an offense is committed, at the Daijosai, or when an unmarried prince or princess departs the imperial palace to visit Ise Shrine or the Kamo Shrines. The December 30 ritual is sometimes held on New Year's Eve.
History
The primary theory is that the Ōharae-shiki began at the end of the seventh century. It evolved over time, especially through the fifteenth century. These changes were linked to modifications to the Ritsuryō system, a set of laws and rules, in the eighth century.The Ōharae-shiki changed again in the Edo period, and some previous aspects were reestablished during the Meiji period.
Purification became more important to prepare for this ritual and became more prominent in the Meiji restoration.