大毘盧遮那成佛經疏 1.29

1.29

經云「祕密主！我說諸法如是。令彼諸菩薩眾，菩提心清淨，知識其心」者，佛已開示淨菩提，略明三句大宗竟，即統論一部始終無量方便，皆為令諸菩薩菩提心清淨知識其心。如此經者，當知一切脩多羅意皆同在此。如釋迦如來所說法者，當知十方三世一切如來種種因緣隨宜演說法，無非為此三句法門，究竟同歸本無異轍。故云「我說諸法如是，乃至知識其心」也。

The sūtra says: 'Master of Secrets! I expound the phenomena in this way so that those assemblies of bodhisattvas may have their bodhicitta purified and know and recognize their mind.' Having revealed the pure bodhi and briefly elucidated the three great core phrases, the Buddha then treats the entire text from beginning to end: its immeasurable upāyas are all meant to cause bodhisattvas to have their bodhicitta purified and know and recognize their mind. Like this sūtra, one should know that the intent of all sūtras is identically here. Just as with the Dharma expounded by Śākyamuni Tathāgata, one should know that the Dharma expounded by all Tathāgatas of the ten directions and three times through various causes and conditions in accordance with capacity is nothing other than this gateway of the three phrases, ultimately returning to the same source without any divergent tracks. Therefore it says: 'I expound the phenomena in this way, down to knowing and recognizing their mind.'