Yogi thinks the blankness or thoughtlessness in his samadhis as Brahman.+

Sage Sankara said:~ -Neither by the practice of yoga nor philosophy, nor by good works nor by learning, does liberation come, but only through the realization that Atman and Brahman are one in no other way. (1) Vivekachoodamani v 56, pg~25

Sage Sankara’s wisdom is nothing to do with religion and yoga. There are two kinds of audiences - the ordinary ones who desire the transitory heaven and other pleasures obtained as a result of ritual sacrifices, and the more advanced seeker who seeks to know the truth beyond the form, time, and space. Religion and yoga are meant for the first audience, to help lead their followers along the way. 

In Yogic Samadhi, the yogi is unaware of the universe, and hence of the ultimate truth or Brahman. To talk of Brahman without knowing the meaning of the universe is like utterly meaningless. Nirvikalpa gives only the idea of the Soul but not the truth of the whole.

Yogi thinks, of the blankness or thoughtlessness in his samadhis as Brahman.  It is not enough to see a mere blank, Nirvikalpa. You have to see the ‘Soul’ the universal Self, which is the cause of the world in which you exist and it itself is uncaused.

 The Soul, the innermost Self is free from ignorance not when it sees nothing at all, as in Yogic Samadhi but only when it sees this entire universe in itself. Hence, there is a need to know

“What is this universe?”

The attention must be drawn to the external world. Advaitic wisdom is the only weapon to bring peace, love and harmony, and universal welfare. This is the highest aim of Advaita to realize the world in its essence is Advaita.

It is no use seeing the personal God everywhere. You must see the Soul, which is present in the form of consciousness everywhere, and then you will be able to treat the world in which you exist as consciousness.

Panchadasi: ~ the impossibility of yoga arriving at a successful end to its practices.  P.509 v, 109

The ‘Self-realization' through yoga is not philosophic. Every yogi who shuts himself in a cave is not thereby freed from thinking. 

Yoga can lead only to temporary peace because the world is subject to change. Only Self- knowledge or Brahma Gnana or Atma Gnana can yield Advaitic awareness in the midst of the form, time,  and space. :~Santthosh Kumaar