大毘盧遮那成佛經疏 10.13

10.13

此真言以阿（長）字為體，阿（長）本不生體，今此阿（長）是第二聲，即是空義。以本不生故同於虛空也，即是一切法皆等於虛空，自得如是了知也。雜色衣，即是種種萬德莊嚴法門。若人能證此空三昧，即能萬德莊嚴其身，如淨虛空明覩顯色也。餘准前說。

This mantra takes the syllable Ā (long) as its essence. Ā (long) has the essence of the originally unborn; here this Ā (long) is the second vowel [sound], which is the meaning of emptiness. Because it is originally unborn, it is identical to space; that is, all phenomena are equal to space, and one personally attains such comprehension. The variegated garments are the Dharma gateways adorned with the myriad virtues. If a person can realize this emptiness-samādhi, they will be able to adorn their body with the myriad virtues, like clearly beholding manifest colors in the pure sky. The rest is as explained before.