大方廣圓覺修多羅了義經略疏 2.1095

2.1095

如善財南邁、普賢西遊等也。《涅槃經》說：是具足因緣故。故《法句經》說：善知識如父母、眼目、脚足、梯蹬、衣食、鎧繩、藥刃等。乃至云：善男子！善知識有如是無量功德，是故我今教汝親近。大眾聞已，舉聲號哭等。

This is like Sudhana traveling south and Samantabhadra journeying west. The Mahāparinirvāṇa-sūtra explains: this is because it is a complete set of causes and conditions. Hence the Dharmapada-sūtra explains: a good spiritual friend is like parents, eyes, feet, a ladder, food and clothing, armor and ropes, medicine and blades, and so forth. It even says: 'Good sons! A good spiritual friend possesses such immeasurable merits; therefore I now teach you to draw close to them.' Having heard this, the great assembly wept aloud, and so forth.