The Self-Knowledge or Brahma Gnana or Atma Gnana brings liberation from experiencing the duality(waking) as reality.

Considering the waking entity or   ego  as self is the main obstacles to recognize the true self.  Formless soul is the real self. First, one must realize the self is neither the waking entity nor the self is dream entity but the self the formless soul.  the soul is present in the form of consciousness. the formless soul is the witness. the formless soul witnesses the three states without the physical apparatus. formless soul is the formless substance and witness and the source of the three stats. 

The truth should become infinite and due to that, the untruth should be destroyed through Self-Knowledge or Brahma Gnana  or Atma Gnana. The Self-Knowledge or Brahma Gnana  or Atma Gnana brings liberation from experiencing the duality(waking)  as reality. This is the only way. Without the attachment to the soul, the innermost self, one cannot detach his-self from the illusory  duality. Without light the darkness cannot go.

The bond on the soul, the innermost self can alone cut these  illusory worldly bonds. Veda says to cut the bond with the wife, to cut the bond with the children and to cut the bond with the wealth. but it is impossible to cut bond with duality without wisdom.
 

Sage Sri,  Sankara says:-  

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) VivekaChudamani v 56, pg 25

Sage Sri, Sankara goes on to say(VC):-

A sickness of not cured by saying the word “medicine.” You must take the medicine. Liberation does not come by merely saying the word “Brahman.” Brahman must be experienced. Until you allow this apparent universe to dissolve from your consciousness, until you have experienced Brahman, how can you find liberation just by saying the word Brahman? The result is merely a noise. Until a man has destroyed his enemies and taken possession of the splendour and wealth of the kingdom, he cannot become a king by simply saying “I am a king.”

A buried treasure is not uncovered by merely uttering the words: “Come forth.” You must follow the right directions, dig, remove the stones and earth from above it, and then make it your own. In the same way, the pure truth of the Atman, which is buried under Maya and the effects of Maya, can be reached by meditation, contemplation, and other spiritual disciplines but never by subtle arguments. (2)

 

Wisdom dawns only when ignorance vanishes. Ignorance vanishes only when the waking entity (ego) becomes aware of the fact that, it itself is not the self. Thus by practicing meditation on the false self within the false experience is like try to catch fish in desert sand.

In one word cut the bond with the three states. Three states are the illusory form of the soul. Without recognizing the soul as self, all the detachment to the duality is impossible task.

Gnani does not mean a scriptural scholar or religious person. One who have detached his –self from three states and immersed in conviction that the soul as self is liberated from experiencing duality as reality in the midst of the duality. One in millions can only acquire Self-Knowledge or Brahma Gnana  or Atma Gnana. 
 

Sage Sri, Sankara's commentary:-

Page 489: "The knower of Brahman (self-realized or Gnani) wears no signs.  Page 500 asks in effect "Tell us what you know, show it, and let us examine it under the mental microscope." It means we must bring notions and beliefs out of vagueness into clearness. It also criticizes the mystics who claim superior knowledge but who cannot communicate it for purposes of verification.

On page 482: On Gnani: "The knower of Brahman wears no signs. Gives up the insignia of a monk's life,…his signs are not manifest, nor his behavior." 

Gaudapada declares : - The merciful Veda teaches karma and Upasana to people of lower and middling intellect, while Jnana is taught to those of higher intellect.

It means the people who follow religion and worship of guru and conceptual god are lower and middling intellect.  But in this modern world people are sharp enough to understand and assimilate ultimate truth or Brahman or god. Thus it is high time to discard the lower knowledge and move ahead to realize the ultimate truth, which is Brahman or God.   

Upanishads declares:- They alone in this world are endowed with the highest wisdom who are firm in their conviction of the sameness and birthlessness of Atman. The ordinary man does not understand their way. (Chapter IV — Alatasanti Prakarana 95-P-188 in Upanishads by Nikilanada)

Therefore, if one is seeking truth he has to know his true self is not physical but it is the Atman, which is in the form of consciousness.