俱舍論疏 2.84

2.84

論「身等色根至如珠寶光」，釋五根俱非也。離身支節無根故，不成二分，非所斫也。如珠寶等光，故非能斫。

On the text of the treatise: "The material faculties of the body and so forth… like the light of a jewel": This explains that the five faculties are neither. Because there are no faculties detached from the bodily limbs, they do not become two portions, and thus are not that which is cut. Like the light of jewels and the like, they are therefore not that which cuts.