Tsukuyomi, the Japanese kami of the Moon in the Kojiki and Nihon Shoki
Tsukuyomi in Japanese mythology: his birth from the eye of Izanagi, the realm of night, the break with Amaterasu and the lunar shrines of Ise.
Among the great deities of Japanese mythology, Tsukuyomi is perhaps the most silent. God of the Moon and brother of the sun goddess Amaterasu, he appears in few episodes and hardly speaks. Yet his name, which can be understood as «he who counts the moons» or «the Moon of the night», and his separation from his sister explain, in the mythical narrative, why day and night never meet.
Born from purification
The main sources are the Kojiki, «Record of Ancient Matters», completed in 712, and the Nihon Shoki, «Chronicles of Japan», of 720. Both were composed at the imperial court and gather older myths, arranged to support the divine descent of the ruling house. In them the story of Tsukuyomi is linked to that of the primordial couple, Izanagi and Izanami, who had given shape to the islands of Japan.
According to the Kojiki, Izanagi returned from the land of the dead, Yomi, where he had vainly sought his dead wife, and purified himself in a river. From his left eye, as he washed, Amaterasu was born, from his right eye Tsukuyomi, from his nose Susanoo, the storm god. Izanagi assigned the heavens to Amaterasu, the realm of night to Tsukuyomi and the sea to Susanoo. They are regarded as the god's three noblest children, and the fact that Sun and Moon are born from the eyes recalls the ancient idea of the heavenly bodies as the eyes of the sky.
The crime and the separation
The Nihon Shoki preserves, in one of its variants, an episode that explains the estrangement between Sun and Moon. Amaterasu sent Tsukuyomi to visit Ukemochi, a deity of food. To welcome him, she produced rice, fish and game from her own mouth. Tsukuyomi, disgusted, killed her with his sword. From the goddess's body there then came forth cattle, silkworms and the various kinds of grain.
When Amaterasu learned of the crime, she grew angry and declared that she no longer wished to see her brother. From that moment, the tale concludes, the Sun and the Moon have lived apart, separated by a day and a night. It is interesting to note that in the Kojiki a very similar episode is attributed instead to Susanoo and another food goddess, a sign of a fluid tradition collected in different versions.
Shrines and moon-viewing
Unlike Amaterasu, Tsukuyomi did not receive a major imperial cult. There are nonetheless shrines dedicated to him, including two minor shrines connected with the great complex of Ise, the most important sacred site of Shinto, and a shrine in Kyoto in the Matsunoo area. In these places the god is worshipped under slightly different names and spellings.
The Japanese relationship with the Moon found expression above all in other forms, such as the autumn viewing of the full Moon, tsukimi, which came from China and spread at court in the Heian period, or the tale of Kaguya-hime, the princess who came from the Moon in the Taketori monogatari, written between the ninth and tenth centuries. Tsukuyomi nevertheless remains the mythical face of the night, the brother whom the Sun no longer wishes to meet.