大方廣佛華嚴經隨疏演義鈔 83.32

83.32

疏「魔王多是大菩薩」者，即《淨名經》，當第二卷〈不思議品〉。因說室包廣坐，皆不思議解脫之力，方便廣說不思議事。迦葉悲歎竟，爾時維摩詰語大迦葉言：「仁者！十方無量阿僧祇世界中作魔王者，多是住不可思議解脫菩薩，以方便力教化眾生，現作魔王。」即其文也。

Regarding the commentary's remark that "The Māra kings are mostly great bodhisattvas": this refers to the Vimalakīrtinirdeśa-sūtra, corresponding to the chapter on the "Inconceivable" in the second fascicle. On the occasion of explaining how the room accommodated the spacious seats, all due to the power of the inconceivable liberation, [Vimalakīrti] extensively explained inconceivable matters by means of upāya. After Kāśyapa finished lamenting in sorrow, Vimalakīrti then spoke to Mahākāśyapa, saying: "Virtuous one, those who act as Māra kings throughout the immeasurable asamyak-world realms of the ten directions are mostly bodhisattvas abiding in the inconceivable liberation, who, through the power of upāya to teach and transform sentient beings, manifest as Māra kings." This is the passage.