Oharae no kotoba (大祓詞)
It was originally a norito that was chanted in Oharae (the great purification) held on the last day of every June and December to purify sins and impurities.
(Here sins refer to those regarded as "sins" in the concept of Shinto and they not necessarily crimes.)
It is also called Nakatomi harae because the Nakatomi clan read the words of purification to the Emperor at the Suzaku-mon Gate in Kyoto. There had been different prayers for June and December ceremonies, but only the one for June survived.
In 'Norito' in Fascicle (Book) 8 of the "Engishiki" (an ancient book for codes and procedures on national rites and prayers), it is described as 'Minazuki-no-tsugomori-no-oharae' (oharae on June 30) with a note 'Follow this procedure in the oharae in December.'
The oharae no kotoba that is used today is based on the norito in "Minazuki-no-tsugomori-no-oharae."
Regarding its origin, KAMO no Mabuchi argued that it could be traced back to the Emperor Tenchi and Emperor Tenmu's era, whereas Norinaga MOTOORI stated that was the Emperor Monmu's era. Both of them stated that the original text existed before the specified era.
At first, the words of the great purification were recited for those assembled for the great purification, but this ritual changed into words presented before the deities. In the medieval period Shinto amalgamated with Onmyodo (Yin-Yang divination) and esoteric Buddhist teachings, and it was believed that by saying these words one could obtain merit similar to those obtainable from the yin-yang spell or Buddhist scriptures. Also, from the belief that the more often these words were recited the more merit one could receive, this ritual was presented by reciting the ritual words thousands or even ten-thousand times. To make the prayer easier to chant, 'Saiyo no nakatomi no harae' (essential words of the purification rituals of the Nakatomi) and 'Saijo no nakatomi no harae' (greatest words of the Purification Ritual of the Nakatomi) were created. These words were especially venerated by Buddhist Shinto and Confucian Shinto scholars, and commentaries of oharae such as "Nakatomi harae kunge" and "Nakatomi harae fusuiso" were written.
Today, the word of purification is chanted by visitors to shrines at oharae. It is also chanted before the alter everyday at shrines under Jinja-Honcho (The Association of Shinto Shrines). In addition to Jinja-Honcho, various denominations of Shinto and some of new religious schools of Shinto Sect use oharae no kotoba. However, the contents have been altered from the description in the Engishiki, so it varies from sect to sect.
Oharae no kotoba can be divided into two parts, the first and latter parts, based on the contents.
The first part starts with the text to order the Imperial family and all the officials participating the ritual to listen to the norito carefully. These are remains of the fact that the original words of purification were meant to be chanted for the participants. Therefore, this part is omitted from the Jinja-Honcho's words of purification today. Then, Japanese Mythology was told from the conquest of Ashihara no nakatsukuni (another word for the country or the location of Japan) to tensonkorin (the descent to earth of the grandson of the sun goddess) and the governance by the grandson. Next, sins committed by the people of the country are listed as 'amatsu-tsumi' (heavenly sins) and 'kunitsu tsumi' (sins other than amatsu-tsumi). And it describes how to purify such sins when they are committed. Because many of these sins don't fit today's concept of 'sin' and some may be considered as discriminatory, the Jinja-Honcho's words of purification only cites 'amatsu-tsumi and kunitsu-tsumi' without mentioning the names of sins.
In the latter part of oharae no kotoba, it is described how sins and impurities are extinguished. The process of extinction of sins and impurities is described with various metaphors, and then how these sins were extinguished by four haraedo no kami (gods for the Great Purification).
Amatsunorito no hutonoritogoto
The last of the first part stated, 'Chant Amatsunorito no hutonoritogoto' (the Heavenly Norito Prayers and the Divination Norito Prayers), but there is no description of the contents of such norito. There have been a discussion on what this term refers to since the Edo Period when the study of Japanese classical literature rose.
Norinaga MOTOORI stated in his "Obarai no kotoba goshaku" (after Explication on the Words of the Great Purification) that the term refers to Oharae no kotoba itself. Kamo no Mabuchi stated a similar opinion in "Norito ko" (On Norito Prayers). The Ministry of Interior that had jurisdiction over Shinto shrines in prewar times adopted this theory, and so does Jinja-Honcho that follows the precedent. Jinja-Honcho decided to place a break between the first and latter parts without citing anything.
There is another theory, however, stating that the term refers to a secret prayer handed down from the age of the gods, and because its secrecy it was not described in the Engishiki. Atsutane HIRATA, who declared himself a posthumous disciple of Norinaga MOTOORI, stated in his unfinished "Koshi-den" that there was a norito called Amatsunorito no hutonoritogoto that had been passed on orally from Amaterasu Omikami (the Sun Goddess) to only the Nakatomi clan. In "Amatsunorito ko" (On Amatsu Norito Prayers), he stated that the norito was the word that Izanagi (The Male Who Invites) said when he performed misogiharae(form of Shinto purification) in Tsukushi no Himuka no Tachibana no Odo no Awakihara. Atsutane showed what was 'Amatsunorito no hutonoritogoto' by researching and gathering prayers for misogiharae that were passed on to many Shinto shrines and sects. The type of 'Amatsunorito no hutonoritogoto' presented by Atsutane is adopted as 'Amatsunorito' by many Shinto groups that don't belong to the Jinja-Honcho. This prayer is chanted between the first and latter sections of Oharaenokotoba as well as used separately as the word for purification.