Yogācārabhūmi Śāstra, Fascicle 34 (66)

Original text: 彼既如是。断能障碍粗品我慢。及于涅槃。摄受增上意乐适悦。便能舍离。后后观心所有加行。住无加行无分别心。彼于尔时。其心似灭而非实灭。似无所缘而非无缘。又于尔时其心寂静。虽似远离而非远离。又于尔时，非美睡眠之所覆盖。唯有分明。无高无下奢摩他行。

Explanation: When a practitioner cultivates to this point, they can eradicate the coarse and heavy arrogance (māna) that obstructs contemplative practice (vipaśyanā-caryā), and further develop intensified aspiration and joyful delight toward nirvāṇa. In this way, they can relinquish all the applied efforts (prayoga) of subsequent contemplative mind, and abide in a non-conceptual mind without applied effort. At this time, the practitioner's mind seems to have ceased but has not actually ceased; it seems to have no object of engagement but is not without engagement. At another time, the practitioner's mind is tranquil; although it seems to have withdrawn from the six sense objects, it has not actually withdrawn. At this time, the practitioner's mind has not yet been covered by pleasant sleep; there is only a very distinct śamatha practice without high or low.

When a practitioner of yoga has eradicated the coarse and heavy arrogance that obstructs direct realization, and has developed intensified aspiration toward nirvāṇa, they no longer need to strive at applied effort. At this time, they feel that the mind seems to be without discrimination, as if it has ceased, but it has not actually ceased; it seems that the mind is not thinking of anything, but in fact there is still perception; they feel that the mind seems to have withdrawn from the realm of sense objects, but it has not actually withdrawn. Moreover, at this time the sleep obstruction has not been eliminated; sleep is still very heavy, and clarity has not yet been attained. There is only a distinct formless mind that does not take up the high or low of dharmas, abiding in meditative concentration (samādhi), without contemplating the four foundations of mindfulness or the Four Noble Truths.