Ignorance is the greatest obstacle to realize the ultimate truth or Brahman

Ignorance is the greatest obstacle to realize the ultimate truth or Brahman.The seeker  has to indulge in deeper self-search  to realize  the fact that,  the self is neither the waking entity nor the self is the dream entity but the self is formless soul, which witnesses the coming and going of the three states in succession without the physical apparatus.  This has to be mentally grasped and assimilated to realize the formless soul, the innermost   self is nothing to do with the three states. On the standpoint of the formless soul, the innermost self, the three states are mere illusion.

The dream ego, dream body and the dream world are reality within the dream but the dream is considered as falsehood when waking takes place. Similarly the waking ego, waking body and waking world are reality within the waking experience but the waking experience also becomes falsehood when wisdom dawns.

Wisdom dawns when the waking entity realizes it itself is not the self in the midst of waking experience.  

Waking experience is state of ignorance. In the state ignorance one remains experiencing illusion as reality.  Till illusion remains reality, he will remain ignorant of the fact that, the cycle of birth, life and death are mere mirage.  Therefore, it is not possible for one to accept the fact that, world is illusion, till  he becomes aware of the fact that , the self is neither the waking entity nor the self is dream entity but the self the formless soul or consciousness ,which is substance and witness of the three states.  Therefore, for those who believe the waking entity as self, and refuse to accept the soul as true self, think that by getting rid of the ego by surrendering to their imaginary source is not the means to self-realization.  One has to realize the fact that, one has to become aware of the existence of the formless witness of the three states, which is the soul, the innermost self.  

The ego, body and the world appear together and they disappear together.   The ego, body and the world are one in essence.

Waking entity is false self within the false experience whereas the self is birthless and deathless because self is formless. Thus surrendering with the false self within the false experience is bound to false surrender. The surrendering is a religious fable meant for the ignorant people.

Sage Sri, Sankara says: - VC-47   All the effects of ignorance, root and branch, are burnt down by the fire of knowledge, which arises from discrimination between these two—the Self and the not-Self. 

One thinks he is imprisoned within this body; whereas the body, ego and his experience of the world are within the mind. The consciousness is hidden within the three states but it is without the three states.  The one, which has the awareness of the three states, is not the body but the soul, which is in the form of consciousness. Thus consciousness is not limited to waking experience alone because it pervades all the three states. Till one views and judges the world-view on base of ego or waking entity, he is in the grip of individuality or intellectuality.  The self is not an individual because it is universal. And it pervades in everything and everywhere in all the three states. Thus individualized judgment will not lead one non-dual destination.  

 That is why  Sage Sri, Sankara says:-VC-65. As a treasure hidden underground requires (for its extraction) competent instruction, excavation, the removal of stones and other such things lying above it and (finally) grasping, but never comes out by being (merely) called out by name, so the transparent Truth of the self, which is hidden by Maya and its effects, is to be attained through the instructions of a knower of Brahman, followed by reflection, meditation and so forth, but not through perverted arguments.

66. Therefore the wise should, as in the case of disease and the like, personally strive by all the means in their power to be free from the bondage of repeated births and deaths.

thus one has to know what is real by realizing our body, ego  and our experience of the world is mere illusion created out of consciousness, which the inner most self.  The nature of the self is emptiness. And it is identified by different masters with different name, such as Brahman, Buddha’s nature, Christ consciousness, Self, Ultimate Truth.

When self becomes aware of its formless non-dual nature it becomes empty of ignorance or illusion or duality or experience of waking or dream.  Thus whatever remains empty of duality or ignorance or illusion is non-dual reality. Only through wisdom one becomes aware of the truth in the midst of duality.

 That is why Sage  "Sri, Sankara said: - 63 -Without causing the objective universe to vanish and without knowing the truth of the Self, how is one to achieve Liberation. 

Universe will not remain as reality when wisdom dawns. Universe is mere mirage created out of consciousness and there is conscious awareness of unity in diversity because there is no second thing exist other than consciousness.