大方廣佛華嚴經隨疏演義鈔 9.34

9.34

疏「本末同時始終一類」者，本是一乘，末即小乘。三乘然非前後，從初得道、迄至涅槃，此三類教同時並行，故云本末同時。言始終一類者，若小始終俱小，若三則始終俱三，若一則始終俱一，故云始終一類，各無異說。「然有三位」下，別出其故。

The commentary's words, "Root and branch are simultaneous, from beginning to end forming one category": the root is the ekayāna, and the branches are the Hīnayāna. The three vehicles are not sequential; from the initial attainment of the Path down to nirvāṇa, these three categories of teachings operate simultaneously in parallel; hence it is said, "root and branch are simultaneous." As for "from beginning to end forming one category": if small, it is small from beginning to end; if three, it is three from beginning to end; if one, it is one from beginning to end. Hence it is said, "from beginning to end forming one category," each without conflicting teachings. Below, from "However, there are three positions...", the commentary specifically brings forth the reason.