分別功德論 4.35

4.35

所以稱尼婆比丘五納為上者，此比丘觀身穢漏三十六物無可貪貴，厭賤此身故，以賤物自障。或說曰：夫衣有可親近者、不可親近者。何者可親近？著惡衣令人羞慚自愧，是可親近；著好衣令人自大奇雅，是不可親近。弊衣助行，是以著五納。此比丘善能內外相況，故稱第一。

The reason why Bhikṣu Nirbhaya was praised as supreme in wearing the five-patch robe is that this bhikṣu contemplated the body's foulness and leaks, its thirty-six substances, as having nothing worthy of greed or value; detesting and despising this body, he shielded himself with despised things. Or it is said: robes are divided into those that may be associated with and those that may not be associated with. Which may be associated with? Wearing bad robes makes one feel shame and self-reproach—these may be associated with; wearing fine robes makes one arrogant and self-important—these may not be associated with. Shabby robes assist practice, and for this reason he wore the five-patch robe. This bhikṣu was skilled at drawing analogies between the internal and external, and was therefore praised as foremost.