When the mind has completely resolved into the Self, then there is non-dual self -awareness.

 Worship of the soul( consciousness), the innermost self in a concrete form is not useful but it is  an obstacle for non-dual realization.

"Non-dual realization is absolutely void of objective knowledge. Such realization nullifies all objective knowledge revealing it in all its nakedness to be as harmless as a picture of a pouncing wild animal.

When the mind has completely resolved into the Self, then there is  non-dual self -awareness. When the wisdom dawns then one realizes the fact that,  the formless soul (consciousness)  is the  innermost self and the waking entity or  'ego ’ is the false self within the false experience (waking)  when one is able to view and judge the three states  on the base of formless soul( consciousness) the innermost self.  

The advanced seeker is aware that his focus of attention is shifted from objectivity towards subjectivity and feels his proximity to the state of non duality. When he actually sinks within the Self, there is no knowledge apart from the non-dual Self- Awareness . This is witnessing awareness.

Waking up, he sees the world just as any other man does but his outlook has become different. He is now able to know his pure Self and no longer confounds himself with the ego.  And he is fully aware of the fact that, the whole experience of diversity(waking)  as consciousness. Because the formless substance and witness of the three states is consciousness.  Thus there is no second thing exist other then consciousness. That is the acme of Realization.

Intellectual and theoretical knowledge consists in differentiating between the Self and the non-Self through a study of the Scriptures, or the teachings of a guru or sage, or by one's own deliberation.

Non-dual wisdom is that which puts an end to the sense of non-Self once for all. Non-dual realization admits nothing unknown or unknowable and pervades everything in entirety so that it cannot in any way be transcended, (e.g., a mirror and the images). 

When that is accomplished, the intellect becomes quite clear because all doubts have been destroyed; doubts and confusion are part and parcel of duality(waking) are destroyed though any remnants of these that may remain are as harmless as a fangless viper.

There is an end of misery in sleep; but the potentiality of misery is not ended. Realization of the true self destroys the cause of misery and sets the one free for ever.