The world is illusion, it includes birth, life and death, which happens within the world. Thus the seekers main aim is to mentally trace the formless substance of the illusion, which is also the witness of the illusion.

Sage Sri, Sankara's commentary to Brahma Sutras (Chap.3.4.50) shows that the Gnani "should pass through life", not run away from life and should take a middle course between seeking worldly honor and worldly abasement. 

Sage Sri, Sankara varied his practical advice and doctrinal teaching according to the people he was amongst. He never advised them to give up their particular religion or beliefs or metaphysics completely; he only told them to give up the worst features of abuse: at the same time he showed just one step forward towards the truth.  Sri, Sankara was extremely precise and careful in his choice of words. 

Sage Sri, Sankara' gave religious, ritual or dogmatic instruction to the mass but pure philosophy only to the few who could rise to it. Hence the interpretation of his writings by commentators is often confusing because they mix up the two viewpoints. Thus they may assert that ritual is a means of realizing Brahman, which is absurd. 

Sage Sri, Sankara believed that those of superior intelligence, have no need of this idea of divine causality, and can therefore dispense with Sruti and arrive at the truth of Non-Dualism by pure reason. 

Sage Sri, Sankara says:-  The world is illusion, it includes birth, life and death, which happens within the world.  Thus the seekers main aim is to mentally trace the formless substance of the illusion, which is also the witness of the illusion. The formless substance and witness of the illusion (world) is the Ataman, and this Ataman itself is Brahman. This Brahman cannot be attained by indulging in egocentric religious orthodoxy. 

The three states have no separate existence apart the source from where they arise and subside.  The source itself is the true self. the soul is the true self.  The soul, which is present in the form of consciousness  is the formless knower of three states which comes and goes in succession.   

waking entity is is not the self but the self is the formless soul. Many people are not even aware what is soul; though knowing of it, many do not comprehend. Only few expound the knowledge of consciousness and very rare assimilate and realize it.  It is all because of their inborn and inherieted conditioning. 

There is a need to dismantle the inherited physical structure mentally to overcome the duality. The whole physical structure is built on the foundation of the ‘I’. Since they think the ‘I’ as self , it becomes difficult to grasp and assimilate and realize the non-dualistic or Advaitc  truth.

The ‘I’, appears and disappears as mind. The mind is in the form of the universe.  The universe appears as waking or dream and disappears as deep sleep. The three states are impermanent. The  formless soul is the  knower of the ‘I’. Since people think whatever  propagated by the  sages in the past as ultimate truth and blindly accept them  as truth, without verifying the validity of their preaching. This blind acceptance becomes a big hindrance in pursuit of truth. If one is seeking truth, one has to verify the validity of any claim through deeper self-search, and accept only verified  un -contradictable truth.

Self-knowledge or Brahma Gnana or Atma Gnana when shared by an unqualified person is not easily comprehended, because it is diversely regarded by disputants. But when it is shared by A Gnani, there can remain no more doubt about It. Ultimate truth is subtler than the subtlest and not to be known through argument.

Self- Knowledge or Brahma Gnana or Atma Gnana cannot be attained by egocentric reasoning. ultimate truth or Brahman becomes easy of comprehension, soul-centric reasoning. One has to attain Self- Knowledge or Brahma Gnana or Atma Gnana right now in this very life not in the next world or the next life.

A Gnani, by means of concentration on the soul, the innermost self, realizes that ancient, effulgent hidden and which dwells and pervades in everything and everywhere in all the three states as its formless substance and witness.

The knowing the soul, the innermost self  is not born; It does not die. It has not sprung from anything; nothing has sprung from It. Birthless, eternal, everlasting and ancient, it is not killed when the body is killed or when the world disappears.  If the murderer thinks he kills and if the killed man thinks he is killed, neither of these apprehends aright. The Self kills not, nor is it killed.

the soul, the innermost self  exists in smaller than the small, greater than the great, and is hidden within the three states as its formless substance and witness. A man who is free from viewing and judging the three states  on the base of ‘I’ beholds the self through self-awareness and becomes free from experiencing the duality as reality.

A Gnani, having realized Consciousness as dwelling within impermanent states is bodiless, pervades the three states as its formless substance and witness and permanent and eternal.

Self-knowledge or Brahma Gnana or Atma Gnana cannot be acquired by the study of the scriptures, or by intelligence, or by much hearing of sacred books. It is attained by him alone whom It chooses. To such a one Consciousness reveals its own form.

He who has not rectified his reasoning  base from the ‘I’(form) base to the soul (formless) base , who does not have the intense urge to know the non-dualistic or Advaitic truth and who is not tranquil and subdued and whose mind is not receptive , cannot acquire Self-Knowledge or Brahma Gnana or Atma Gnana. It is realized only through soul-centric reasoning .

Ultimate truth or Brahman  is not known by those who know it; it is known by those who do not know it.  That is when one says he knows the ultimate truth or Brahman; he is saying it as a person. 

The Consciousness cannot be applied only to the individuality but to the whole experience (three states). But in reality the person and world created out of consciousness, thus nothing exits other than consciousness. One must know Consciousness as the formless clay of the three states (whole).

Ultimate truth or Brahman  is known when it is realized in every state of mind; for by such Knowledge one attains Immortality. Through Self-knowledge or Brahma Gnana or Atma Gnana  one attains self-awareness in the midst of duality.