大方廣圓覺修多羅了義經略疏 1.192

1.192

序中證信便是發起，謂佛入大光明藏，與一切佛同住眾生清淨覺地，現諸淨土。菩薩主伴皆入三昧，同一佛境，以表因果無異、凡聖同源，顯發此經旨趣如是。

In the preface, confirming faith is precisely launching the teaching: the Buddha enters the treasury of great radiance, dwelling with all buddhas in the pure ground of enlightenment of sentient beings, manifesting various pure lands. The bodhisattvas, host and retinue alike, all enter samādhi, sharing the identical realm of the Buddha, so as to express that cause and effect are not different, and that ordinary beings and sages share the same source, revealing that the purport and orientation of this sūtra are thus.