Yoga Sūtra Chapter Four verse 22

चितेरप्रतिसंक्रमायाः तदाकारापत्तौ स्वबुद्धि संवेदनम् ॥२२॥

citeḥ apratisaṃkramāyāḥ tat-ākāra-āpattau sva-buddhi-saṃvedanam ||22||

Entering that appearance of non-changing awareness,
is experience of own comprehension.

cit - awareness, consciousness; to be aware of; to cause to comprehend, to observe; perceiveapratisaṃkrama - non-changing; having no intermixturetat - that, thisākāra - form, figure, shape, stature, appearance, external gesture or aspect of the body, expression of the faceāpatti - happening, occurring; entering into a state or condition, entering into relationship with, changing intosva - own; one's self, one's own, my own, thy own, his own, her own, our own, their ownbuddhi - the intellectual faculty; comprehension; intelligence, discernment, judgementsaṃvedana - to fully experience; completely knowing

Commentaries and Reflections

Commentary by S Ramaswami:

“The Puruṣa gets the experience of the object because it falls onto the Buddhi and the Buddhi is transformed. By his mere presence the Puruṣa observes the Buddhi into which the object has fallen.
Thus there is no direct perception by Puruṣa. The Puruṣa observes the Cittavṛtti. The Cittavṛtti is a combination of one’s Citta and the object.
Due to the presence of Puruṣa the Citta assumes the likeness of consciousness and operates.
However the Puruṣa and Cit does not change. It has been said:
‘The cave where the eternal Bramma resides, it situated neither in the world nor in the mountain chasm, nor in the darkness, nor in the cavern of the deep sea. The sages know it (the cave) to be the modifications of the Buddhi indistinguishable from metempiric consciousness.'”.