四分律行事鈔資持記 3.245

3.245

六中，壞色異俗，折破非衣，故竝入輕。猶是下，反上二種故重。儀云：為絕懷俗之心故。襦，短衣也。

In the sixth: corrupted colour differs from the secular, and torn up it is no longer a garment, so both are reckoned as light. Below "still being", it is the reverse of the two kinds above, hence heavy. The Ceremonial Standard states: "In order to sever the secular mindset." A rú is a short garment.