大毘盧遮那成佛經疏 10.19

10.19

吽，是恐怖義，以大猛威自在之力怖彼三重塵障，令得除淨而同佛眼。惹，此最後字，是種子也。諸字皆為釋此字義，即生不生是闍字義也。或以初薩字為體，亦同用之，是驚覺義也。吽字中有訶字是歡喜義，上有大空點是三昧，下有三昧畫。此中下畫字亦三昧，二三昧中行也。三世諸佛皆同此觀，故名等觀也。

Hūṃ has the meaning of terror: through the power of great wrathful sovereignty, it terrifies those three layers of defilement hindrances, causing them to be purified and made identical to the Buddha Eye. Jaḥ, this final syllable, is the bīja. All syllables explain the meaning of this syllable; that is, arising and non-arising is the meaning of the syllable ja. Alternatively, taking the initial syllable sa as the essence, it is also used in the same way, having the meaning of awakening. Within the syllable hūṃ there is the syllable ha, which has the meaning of joy; above it is the dot of great emptiness, which is samādhi; below it is the stroke of samādhi. The lower stroke here is also samādhi, practicing within the two samādhis. The Buddhas of the three times all share this contemplation; hence it is called equal contemplation.