大毘盧遮那成佛經疏 3.27

3.27

經云「為彼從初發心乃至十地諸菩薩」者，謂初發淨菩提心時，見此漫荼羅已遍法界。昇第二住，又逾廣逾深。作十轉開明，乃至第十一地而後所見圓極。如是安布分位已，即皆遍至十方，於自法界門施作真言事業、示現進修次第、教授眾生，此相現前了了無礙。下文所說，但開出此心作名字流通耳。又令普現隨類身，而言悉現如來身者，明本迹俱不思議、加持不二，豈欲令獨一法界作種種形耶？行者如是解時，觀毘盧遮那與鬼畜等尊，其心平等無勝劣之想，輒從一門而入皆見心王。是故作佛事已，經云「遍至十方，還來入佛身本位，本位中住而復還入。」意明一切方便畢竟同歸也。

Regarding the sūtra saying, "For those bodhisattvas from the initial arousal of the mind up to the ten bhūmis": this means that when initially arousing the pure bodhicitta, one sees this maṇḍala already pervading the dharmadhātu. Ascending to the second abode, it becomes still broader and deeper. It unfolds in ten turning illuminations, until in the eleventh bhūmi what is seen reaches ultimate perfection. Having laid out the divisions and positions in this way, they then universally reach the ten directions, performing mantra activities at their own dharmadhātu gateways, demonstrating the stages of progress in practice, and instructing sentient beings, with these marks appearing clearly and unimpeded. What is stated below merely opens up this mind to circulate it in names. Furthermore, having them universally manifest bodies conforming to different kinds, while saying that "all manifested bodies of the Tathāgata," clarifies that origin and traces are both inconceivable, and adhiṣṭhāna is non-dual; how could it mean that the singular dharmadhātu merely takes on diverse forms? When the practitioner understands in this way, contemplating Vairocana and spirits, animals, and so forth with equal veneration, their mind is impartial, without notions of superiority or inferiority; whenever entering through a single gateway, they see the mind-king. Therefore, after performing Buddha activities, the sūtra says, "universally reaching the ten directions, they return and enter the Buddha body's original position, and having dwelt within the original position, they enter again." The intention is to clarify that all upāyas ultimately return to the same [source].