妙法蓮華經玄義 4.121

4.121

三十三天者，一名住善法堂天。昔持七戒，堅固無嫌，施四果、病人、父母、入滅定人。慈、悲、喜、捨，與怖畏壽命，生善法堂天，作釋迦提婆，姓憍尸迦，名能天主。有九十九那由他天女為眷屬，心無嫉妬，善法堂廣五百由旬。

Regarding the Heaven of the Thirty-Three, the first is named the Heaven Dwelling in the Good Dharma Hall. In the past, they observed the seven precepts firmly and blamelessly, gave to the [attainers of the] four fruits, the sick, parents, and persons entering the cessation absorption. With benevolence, compassion, sympathetic joy, and equanimity, they gave fearlessness and life, thus being born in the Good Dharma Hall Heaven to become Śakra Devānām [Indra], with the family name Kauśika and named Capable Heavenly Lord. He has ninety-nine nayutas of heavenly maidens as his retinue, his mind is free of jealousy, and the Good Dharma Hall is five hundred yojanas wide.