The Vedanta Sutras of Badarayana, Commentary by Sankara (SBE38), tr. by George Thibaut  at sacred-texts.com
24. And in the state of perfect conciliation also (the Yogins apprehend the highest Brahman), according to Sruti and Smriti.
At the time of perfect conciliation the Yogins see the unevolved Self free from all plurality. By 'perfect conciliation' we understand the presentation before the mind (of the highest Self), which is effected through meditation and devotion.--This is vouched for by Sruti as well as
[paragraph continues] Smriti. So, e.g. Ka. Up. IV, 1, 'The Self-existent pierced the openings of the senses so that they turn outward; therefore man looks without, not within himself. Some wise man, however, with his eyes closed and wishing for immortality, saw the Self within.' And Mu. Up. III, 1, 8, 'When a man's mind has become purified by the serene light of knowledge then he sees him, meditating on him as without parts.' Smriti-passages of the same tendency are the following ones, 'He who is seen as light by the Yogins meditating on him sleepless, with suspended breath, with contented minds, with subdued senses; reverence be to him 1!' and 'The Yogins see him, the august, eternal one.'
But if in the state of perfect conciliation there is a being to be conciliated and a being conciliating, does not this Involve the distinction of a higher and a lower Self?--No, the next Sûtra replies.
172:1 Whose Self is Yoga.