俱舍論記 4.63

4.63

「能順覺支至心輕安故」者，經部通難。此身輕安風雖是有漏，能順覺支，心輕安故，名為覺支亦無有失。如何順者？由入定故，身中即有輕安風起，能引覺支心輕安故，此即同時說名能引。由斯相順，故名覺支。

"Because it can accord with the factor of awakening... mental pliancy": the Sautrāntika resolves the objection. Although this tactile wind of bodily pliancy is sāsrava, because it can accord with the factor of awakening, mental pliancy, there is no error in calling it a factor of awakening. How does it accord? Because of entering concentration, the wind of pliancy arises in the body, being able to induce the mental pliancy that is a factor of awakening; thus, arising at the same time, it is called able to induce it. Because of this concordance, it is therefore called a factor of awakening.