菩薩從兜術天降神母胎說廣普經 2.26

2.26

佛言：「過去恒河沙諸佛世尊，名字假號不可勝記，亦如眾生生生不滅，無邊無際亦無端緒，諸佛要集心如空界，涅槃者即眾生是也。是故如來不入涅槃。何以故？為眾生故。」

The Buddha said: "The names and designations of the past Buddhas, Bhagavats, as numerous as the sands of the Ganges, are beyond reckoning. Just as sentient beings are born and reborn without ceasing, boundless, limitless, and without beginning, the essential unified mind of the Buddhas is like the realm of empty space. That which is nirvāṇa is precisely sentient beings. Therefore the Tathāgata does not enter nirvāṇa. Why is that? For the sake of sentient beings."