大毘盧遮那成佛經疏 13.26

13.26

此是真言之心，一切法本來不生。上又有點，即是大空遍一切處也。此大寂涅槃之體性，萬德寂然，遍一切處也。

This is the heart of the mantra: all dharmas are originally unborn. Above, there is also a dot, which is the great emptiness pervading all places. This is the essential nature of the great, tranquil nirvāṇa: myriad virtues are serene and pervade all places.