大方廣佛華嚴經隨疏演義鈔 72.40

72.40

疏「上句無量則盡法界之疆域」者，即經「虛空界廣大三昧」，此同自受用剎。下句「窮國土之體性」，即法性土，此能窮究。

Regarding the commentary's 'The upper phrase "immeasurable" exhausts the boundaries of the dharmadhātu': this is the sūtra's 'vast samādhi of the space-realm', which corresponds to the realm of self-enjoyment. The lower phrase 'fathoming the essential nature of the lands' refers to the dharmatā-land, which this [samādhi] is able to fathom completely.