觀音義疏 2.66

2.66

自在天是欲界頂，具云婆舍跋提，此云他化自在，假他所作以成己樂，即是魔主也。《淨名》云：「多是不思議解脫。」菩薩住赤色三昧，不取、不捨，應為魔王，令諸魔界即是佛界，四句現身，以權引實。

The god of Mastery (Vaśavartin) is the pinnacle of the desire realm. In full it is Paranirmita-vaśavartin, translated here as 'taking mastery over the transformations of others'. Borrowing what is produced by others to complete his own pleasure, he is the lord of Māras. The Jingming jing says: 'Mostly they possess inconceivable liberation.' The bodhisattva abides in the red-colour samādhi, neither grasping nor relinquishing; responding as the Māra king, he causes all māra realms to be none other than the Buddha realm, manifests a body through the four propositions, and leads to the real by means of the provisional.