Yen Wang of China, Emma-o of Japan—originally Yama, the Hindu god of death—was imported as part of Buddhist mythology. His task was the enforcement of the law of retribution, but the idea that the wheel of rebirth operated automatically outmoded an infernal judgement, leaving ‘the king of the devils’ as tormentor of the most abominable souls. In China he merged with indigenous traditions about the place of death, the Yellow Springs, huang ch'uan. This dreary abode was not unlike our own world, and miners were always worried that they might accidentally break into it. The earliest records of ancestor worship reveal that there was fear of the family spirits; inscriptions are often inquiries as to whether particular illnesses or misfortunes were or were not being caused by dissatisfied ancestors.
In Japan the dark-faced god of death rules over a kingdom thought to be the exact opposite of the Paradise of the Pure Land. The antithesis of Amida-nyorai, Emma-o is the pitiless judge, unswayed by the solicitude of Jizo-bosatsu. Hence the popular proverb: ‘Borrow with Jizo's face, but repay with look of Emma.’