大方廣佛華嚴經隨疏演義鈔 22.3

22.3

疏「竪通四土」等者，並如〈世界成就品〉。略言竪者，即於一處有四土故。以法性之土為三土體，故本遍常。自受用土量周法界，一如法性。他受用土及變化土不離上二，猶如物影不離空及日光。而他受用及變化土，隨心異見，亦如兩影互相涉入，故一塵中則有四土。橫遍法界，即十方一切差別國土。「橫竪相融」者，以竪融橫則一塵之中有十方國土，以橫融竪則一塵四土常遍十方。結成可知。

Regarding the commentary's "vertically penetrating the four lands," and so on: these are all as in the "Chapter on the Formation of the World." To speak briefly of the vertical: it means that in a single place there are four lands. Since the land of dharmatā is the substance of the [other] three lands, it is fundamentally pervasive and permanent. The land of personal enjoyment has a measure that encompasses the dharmadhātu, identical to dharmatā. The land of enjoyment for others and the transformation land are not separate from the above two, just as the shadow of an object is not separate from space and sunlight. Moreover, the land of enjoyment for others and the transformation land, being seen differently according to the mind, are also like two shadows interpenetrating each other; therefore, within a single dust mote there are the four lands. Horizontally pervading the dharmadhātu refers to all the distinct lands in the ten directions. As for "the horizontal and vertical blending with each other": fusing the horizontal with the vertical, within a single dust mote there are lands of the ten directions; fusing the vertical with the horizontal, the four lands within a single dust mote constantly pervade the ten directions. The final conclusion may be understood from this.