Ochimizu is water that was said to bring back youth when it was drank. It is one of the mystical medicines related to moon worship for immortal life. It is also described as a part of explaining human morphology.
Tsukuyomi, the moon god in Japanese mythology, is also related to the belief in ochimizu. In "Manyoshu" (Collection of Ten Thousand Leaves), 'Tsukuyomi' appears as someone that has mystical water 'ochimizu' that brings back youth.
A poem in volume 13 goes,
天橋(文) 長雲鴨 高山(文) 高雲鴨 月夜見乃 持有越水 伊取來而 公奉而 越得之(旱)物'
Though Bridge to Heaven is long and Takayama is high, I want to go and get Tsukuyomi's ochimizu and present it to you so that you can regain your youth.
Poem in response goes,
天有哉 月日如 吾思有 君之日異 老落惜文'
天なるや 日月のごとく 我が思へる 君が日に異に 老ゆらく惜しも (3246)
These poems can be seen. They express the sadness of seeing an aging person and a desire to bring back youth by somehow obtaining 'ochimizu' that 'Tsukuyomi' in heaven has and offer it to that person. Several poems that read about 'ochimizu' can be seen in Manyoshu.
吾手本 將卷跡念牟 大夫者 變水白髪生二有'
我が手元 まかむと思はむ ますらをは をち水求め 白髪生ひにたり (Vol. 4, 627)
白髪生流 事者不念 變水者 鹿煮藻闕二毛 求而将行'
白髪生ふる ことは思はず をち水は かにもかくにも 求めてゆかむ (Vol.4, 628)
従古 人之言来流 老人之 變若云水曽 名尓負瀧之瀬'
古ゆ 人の言ひける 老人の をつといふ水ぞ 名に負ふ瀧の瀬 (Vol.6, 1034)
As it can be seen from above, each poem expresses an earnest desire to seek 'ochimizu' that brings back youth to an aged person.
Hideo ARAI, in his paper, 'A Little Thought on 'Ochimizu that Tsukuyomi Has'' (in 'Nihon Bungei Kenkyu' (Japanese Literary Studies), April, 1991) pointed out from the standpoint of folklore that several rituals that obtain 'wakamizu,' which expels evil atmosphere for the year, are performed on New Year's Day in various localities in Japan, and that 'Wakamizu wo sonau' (offering of wakamizu) performed on the first day of spring as an annual event during the Heian period is observed in records such as "The Engishiki" (an ancient book for codes and procedures on national rites and prayers) "Nenchu gyoji hisho" (record of annual events) and issho (lost book) "月舊記." He discusses that as with the seasons that changed in ancient Japan, there existed a belief in the so-called 'wakamizu' that purified the body and the mind and recharged life force by obtaining sacred water 'wakamizu' at the beginning of spring. Furthermore, the belief that views a certain type of water as sacred water that brings back youth can be seen in many places in poems that reads about 'ochimizu' and rejuvenation in Manyoshu. Because it is difficult to think that this is simply a literary expression, he discusses that there existed a belief in 'wakamizu' behind these poetic expressions.
Akariyazagama's water of youth and water of death
The connection between 'the moon and the water that brings back youth' is also mentioned in the ethnic lore of Okinawa that has been included in "Tsuki to Fushi" (moon and immortality) (The Toyo Bunko [Oriental Library]) authored by Nikolai Aleksandrovich Nevskii, a Russian scholar of Asian Studies.
In the ancient times, when people first began to live on Miyako-jima Island, the moon and the sun sent a human named Akariyazagama to earth on the first night of setsusai (festival marking a seasonal change), carrying a bucket of shijimizu (water that brings youth) and a bucket of shinimizu (water that brings death) on a lever.
The intention was to 'give shijimizu to people, shinimizu to snakes.'
However, when he put down the buckets and took a rest stop on the way, a snake appeared and bathed in shijimizu. Left with no choice, he bathed people with shinimizu, which was the opposite of the command. Since then, snakes gained immortal body by molting and undergoing rebirth. On the other hand, people shoulder the fate of dying with a short life.
The compassion of the moon and the sun, in turn, brought about the tragedy of death to humans. However, gods pitied humans, and every year since then, they send 'wakamizu' on the day of the setsusai so that the humans can regain a little bit of their youth. This is the origin of the 'wakamizu' ritual.
The origin of wakamizu belief
In ancient Chinese legends there are many stories of elixirs of rejuvenation. In "Huainanzi" (The Masters, Philosophers of Huainan), there is a story of Koga who stole 'potion of eternal life' that belonged to Seiobo (Queen Mother of the West) and ran to the realm of the moon. It can be seen that such stories of elixirs became the origin of the concept of potions that bring back youth. Stories with similar ideas are widely available throughout the world. James George FRAZER categorized stories of origins of death, he divided them into the 'snakes and molting' group, which is related to animals such as snakes that molt, and the 'getsu eikyo' (waxing and waning of the moon) group that considers a connection between the waning and waxing of the moon and death in humans. The story of Akariyazagama takes the form that combines both, and furthermore, the conclusion of the story is the origin of the wakamizu rituals.
It can be considered that the reason why the moon and immortal life and rebirth have been associated since the ancient times throughout the world is that the waxing and waning of the moon presents an image of god of death and rebirth. The moon repeats the cycle of waxing and waning through the new moon, waxing moon, full moon, waning moon and then the new moon. That is, the moon starts to wane after it passes through the peak called the full moon, then waning moon and finally disappears as a new moon, but it comes back in the night sky as a crescent moon.
This cycle directly evokes death and rebirth, and furthermore, it is considered to be connected to the concept of immortal life and agelessness, giving rise to the belief in 'wakamizu.'