觀彌勒上生兜率天經贊 2.14

2.14

爾時兜率陀天上有五百億天子，一一天子皆修甚深檀波羅蜜，為供養一生補處菩薩故，以天福力造作宮殿。

"At that time, in Tuṣita Heaven, there were five hundred billion devaputras. Each and every devaputra cultivated the profound dāna-pāramitā. For the sake of making offerings to the bodhisattva bound to one last birth, by the power of their divine merit, they constructed palaces."