維摩經略疏 1.19

1.19

問：染淨國名出何經論？答：《思益經》云「日月光佛命梵天來此土云：『汝當用十法遊彼世界，娑婆之土名染淨世界。』」染即是凡，淨即是聖。

Question: In what sūtra or treatise does the name "defiled and pure land" appear? Answer: The Si-yi jing states, "The Buddha Sūryaprabhāsa commanded a Brahmā heaven [king] to come to this land, saying: 'You should travel to that world using ten dharmas; the Sahā land is named the defiled and pure world.'" Defiled is precisely the ordinary, and pure is precisely the sage.