大方廣佛華嚴經隨疏演義鈔 11.20

11.20

疏「事法既爾」下，第二以事所依，例餘所依教等九。謂事法既有百門，二教義為百門、三境智為百門，乃至感應皆具百門，故有千門。

In the commentary, from "Since phenomena are thus" downward, is the second [section]: taking phenomena as the basis to draw the analogy to the other nine bases, such as teaching. That is, since phenomena already have a hundred gates, secondly, teaching and meaning constitute a hundred gates; thirdly, object and cognition constitute a hundred gates; and so on up to stimulus and response, which all possess a hundred gates; hence there are one thousand gates.