瑜伽論記 7.549

7.549

第三、如是乃至有彼前相下，明行漸增，煩惱障遣則有相觀漸漸舒緩者，初起輕安漸捨滅故名舒緩，泰云：得定前狀於已頂上似有重物而起，後便遍身輕安。

Third, from "in this way, up to having those precursor signs" below, it clarifies that as the practice gradually increases and the affliction-hindrances are dispelled, the contemplation with signs gradually slackens; because initial pliancy is gradually relinquished and eliminated, it is called slackening. Tai says: the precursor sign of attaining concentration arises on one's crown as if there were a heavy object, and afterwards pliancy pervades the entire body.