俱舍論頌疏論本 11.74

11.74

已說人間壽量長短，要先建立天上晝夜，方可計算天壽短長。天上云何建立晝夜？且人間五十年為四天王天一晝一夜，乘此晝夜，三十日為月，十二月為年，彼壽五百歲。上五欲天，漸俱增倍，謂人間百歲為第二天一晝一夜，乘此晝夜，成月及年，彼壽千歲。夜摩等四，隨如次人二、四、八百、千六百歲為一晝一夜，乘此晝夜，成月及年，如次彼壽二、四、八千、一萬六千歲。問：「持雙已上日月并無，諸天云何建立晝夜及光明事？」答：「依華開合建立晝夜，又依諸鳥鳴靜差別，或依天眾寤寐不同，依己自身光明成外光明事。」

Having spoken of the length and shortness of human lifespan, one must first establish days and nights in heaven before one can calculate the length and shortness of heavenly lifespan. How are day and night established in heaven? Fifty human years constitute one day and one night for the Cāturmahārājakāyika gods; multiplying this day and night, thirty days make a month, twelve months make a year, and their lifespan is five hundred years. For the five higher desire heavens, they double gradually: one hundred human years is one day and one night for the second heaven; multiplying this day and night to form months and years, their lifespan is a thousand years. For the four heavens beginning with Yāma, successively two, four, eight hundred, and sixteen hundred human years make one day and one night; multiplying these days and nights into months and years, their lifespans are successively two, four, eight thousand, and sixteen thousand years. Question: "Above the Yugandhara [mountains] the sun and moon do not exist; how do those gods establish day, night, and the phenomenon of light?" Answer: "They establish day and night based on the opening and closing of flowers, or based on the distinction of birds singing or falling silent, or based on the waking and sleeping of the gods; they accomplish the external phenomenon of light through the radiance of their own bodies."