The second half of Izanami's myth is one of the most powerful in Japanese religion and turns on the origin of death itself. Grief-stricken, Izanagi follows his wife down into Yomi to bring her back, and finds her in the darkness. She tells him she has already eaten the food of the underworld and may not easily return, but will petition its gods; only, she warns, he must not look at her. Unable to wait, Izanagi lights a torch, and sees that her body has become a rotting, maggot-ridden corpse, with the thunder-kami of decay grown upon her.
Horrified, he flees, and the enraged Izanami, shamed and furious, sends the hags and warriors of Yomi and at last pursues him herself. Izanagi escapes to the upper world and blocks the pass between the living and the dead with a great boulder, and across it the estranged couple exchange their final, terrible words: Izanami vows that she will each day strangle a thousand of the living, and Izanagi answers that he will each day cause fifteen hundred to be born. In this exchange the myth accounts at once for the reality of death and for the fact that the living nonetheless increase. Izanami, once the mother of the world, becomes the great goddess of death and of the underworld, and the ritual purification that Izanagi performs on escaping the pollution of Yomi is remembered as the origin of the central Shinto concern with cleansing and purity.