大方廣圓覺修多羅了義經略疏 2.1097

2.1097

夫善友度人種種方便，師徒心契，法意方傳。是以俯就物機，相親相近。愚者無識，憍慢便生。慢既翳心，即不入道，故云應斷。

A good friend delivers beings through various skillful means; only when master and disciple accord in mind is the Dharma intent transmitted. For this reason, they condescend to accommodate beings' capacities, drawing near and affectionate. The foolish lack discernment, and arrogance instantly arises. Once arrogance obscures the mind, one does not enter the path; hence it is said that one 'should sever [it].'