大方廣圓覺修多羅了義經略疏 2.327

2.327

八、苦樂對，極惡業成，天宮即見地獄；極善業熟，地獄即是天宮。二業之念由心，地獄天宮豈定？心既本空，一切清淨，故《寶積經》有地獄三昧、天宮三昧。然諸法皆爾，非唯天獄，今且約敵體相違之法以例餘。

Eighth, the pair of suffering and bliss. When extreme evil karma is completed, in a heavenly palace one sees hell; when extreme good karma ripens, hell is itself a heavenly palace. The thoughts of these two karmas stem from the mind; how could hells and heavenly palaces be fixed? Since the mind is originally empty, all is pure. Hence the Ratnakūṭa-sūtra has the hell samādhi and the heavenly palace samādhi. Now, all phenomena are like this, not only heavens and hells; here he briefly uses dharmas that directly oppose each other to exemplify the rest.