大毘盧遮那成佛經疏 11.8

11.8

「說極清淨修行法，深廣無盡離分別」者，佛說此極清淨無分別離分別甚深自證之法，此法深廣，不可思議、不可破壞，無有窮盡。即是歎法德之意也。

Regarding "Teaching the practice that is utterly pure, / profound, vast, inexhaustible, and free from conceptualization": the Buddha taught this utterly pure, non-conceptual, discrimination-free, profound Dharma of self-realization; this Dharma is profound, vast, inconceivable, indestructible, and without end. This expresses the praise of the Dharma's virtues.