釋禪波羅蜜次第法門 5.128

5.128

答曰：猶是內淨，於喜樂後，立異名說。所以者何？猗名為縱，縱名為任，既內無垢累，猗任自在，不慮聲刺及覺觀所牽，故言猗。

Answer: It is still internal purity, established under a different name after prīti and sukha. Why is this? 'Pliancy' is called releasing, and releasing is called yielding to freedom; since there are no internal defilements or burdens, one yields to freedom with ease, without anxiety over the thorn of sounds or being dragged away by vitarka and vicāra; therefore it is called pliancy.