俱舍論記 21.18

21.18

「有餘師說至順下分名」者，敘異說。前三能障超下有情不成聖故，後二能令不超下界不生上故，故五皆得順下分名。

Regarding 'Other masters say... the name "fetter belonging to the lower division"', this relates alternative explanations: the first three can obstruct transcendence for sentient beings of the lower realm by preventing them from becoming noble ones, while the latter two cause them not to transcend the lower realm by not being born in higher realms; therefore all five receive the name 'fetter belonging to the lower division'.