量處輕重儀 2.41

2.41

已前三件，並入輕者。由資道正要，聖制令畜，止令隨身，不令欠減。故佛言，所行之處與衣鉢俱，無所顧戀，猶如飛鳥，以此文證，所為處重，非不如法，故入輕收。由並制受持，無緣輒捨，必有違離，俱結正愆。故法衣以覆身，應器以資養，尼師壇具用以安坐，必若乖制，並制有罪。

The reason why the previous three items are all classified as light property is that they are primary essentials for supporting the Way, which the Sage ordained to be kept, requiring only that they be kept on one's person and not allowed to be deficient. Therefore, the Buddha said that wherever one goes, one is together with robes and pātra, without any lingering attachments, just like a flying bird. Using this text as proof, their designated purpose is weighty, not unaccordant with the Dharma; therefore, they are classified as light property. Because they are all ordained to be received and upheld, and must not be casually abandoned without cause, if one is separated from them, it constitutes a principal offense in every case. Thus, the Dharma robes are used to cover the body, the vessel in accordance [with measure] is used for sustenance, and the niṣīdana mat is used for sitting in peace; if one goes against the regulation, it is ordained in all cases to be an offense.