俱舍論記 9.19

9.19

「頌曰至地獄頭歸下」者，此兩行頌明次九門：一明眼境、二行遲疾、三明具根、四明無對、五不可轉、六明所食、七明住時、八明結生心、九明行相。

Regarding "The verse says: ... Hell-beings head downward": these two lines of verse clarify the next nine topics: first, clarifying the range of the eye; second, speed and slowness of travel; third, clarifying completeness of faculties; fourth, clarifying unobstructedness; fifth, irreversibility; sixth, clarifying the food consumed; seventh, clarifying the duration of stay; eighth, the mind of taking rebirth; ninth, the bodily postures of movement.