Great Sūtra of the Conflagration 1.11

1.11

佛言：「諸比丘！如一日月，旋照四天下時，爾所四千天下世界，有千日月、有千須彌山王、有四千天下、四千大海水、四千大龍宮、四千大金翅鳥、四千惡道、四千大惡道、七千種種大樹、八千種種大山、萬種種大泥梨，是名為一小千世界。如一千小世界，爾所小千千世界，是名為中千世界。如一中千世界，爾所中千千世界，是名為三千世界；悉燒成敗，是為一佛剎。」

The Buddha said: "Bhikṣus! Just as a single sun and moon revolve and illuminate the four continents, in that space of four thousand continents there are one thousand suns and moons, one thousand Sumerus, Kings of Mountains, four thousand continents, four thousand great oceans, four thousand great dragon palaces, four thousand great garuḍas, four thousand durgatis, four thousand great durgatis, seven thousand various great trees, eight thousand various great mountains, and ten thousand various great Narakas; this is called a small thousand-world sphere. As is one small world sphere, so a thousand such small thousand-world spheres is called a medium thousandfold world sphere. As is one medium thousandfold world sphere, so a thousand such medium thousandfold world spheres is called a three-thousandfold great thousand-world sphere; it is completely burned, formed, and destroyed, and this is one buddhakṣetra."