OM Asato ma sad gamaya, tamaso ma jyotir gamaya, mrityor ma aamritaam gamaya. Shanti, Shanti, Shanti.+

The seeker's aim is the search for the ultimate truth or Brahman.  the search to find the non-dualistic truth that in actuality never was lost, only hidden by ignorance.

Upanishad aspiration is best expressed in the following sutra:~

OM Asato ma sad gamaya, tamaso ma jyotir gamaya, mrityor ma aamritaam gamaya. Shanti, Shanti, Shanti

"OM Lead me from ignorance to truth, from darkness to light, from death to immortality. Peace, Peace, Peace" (Brhadaranyaka Upanishad (1/3/28)).

The belief system was coherent because they had a transcendent God as a central doctrine, whereas on the non-dualistic perspective god cannot be considered as the center. 

First, one should not hold a God as the center of existence without verification. Both the theist and atheist theories have nothing to do with ultimate truth or Brahman or God in truth. 

 

 God based on blind belief is not God in truth. Holding God based on blind belief is holding an illusory universe as reality because the belief is possible only within the realm of the illusory universe. 

Duality is merely an illusion from the ultimate standpoint.  Without  God based on blind belief, the belief system holds no water.  God based on blind belief is not God in truth. 

Belief needs a believer.  The believer needs to be born in this world. If the believer is born than he is part of the illusion.   

Without the believer, there is no belief.  The believer and his world and his belief of GOD are part of the illusion because the Self is birth-less because the Self is invisible and nondual. The one, which is born, lives and dies, is not the Self.    

The Soul, the Self is an invisible substance and witness of the illusory universe. The Soul, the Self, which is present in the form of consciousness, is the ultimate truth or Brahman or God in truth or God in truth.  

The seeker has to become aware of the existence of the formless witness apart from the three states. The formless witness is the soul, the innermost self, which witnesses the coming and going of the three states. 

The seeker  has to indulge in deeper self-search to realize that the Self is neither the waking entity(you)  nor the self is a dream entity,  but the self is a formless Soul, which witnesses the coming and going of the three states, in succession. 

This truth  has to be mentally grasped and assimilated to realize the invisible Soul, the Self is nothing to do with the three states. From the standpoint of the formless Soul, the Self, the three states are merely an illusion. 

Till you realize you and your world are made of the same stuff.  And that stuff is Soul, which is present in the form of consciousness, the Soul, the Self remains in the web of ignorance. 

When the Soul wakes up in its own awareness, the illusory form, time and space, become one with the nature of the soul. In Self-awareness, there is neither you, nor me, nor others,  nor the world, because there is unity in diversity. That is oneness in the midst of the dualistic illusion or Maya.  

Thus, you have to realize the fact that, the whole universe in which you exist is made of the single stuff is very much necessary to realize the Advaitic truth, which is beyond the form time and space.

The mind becomes still when ignorance vanishes. Ignorance vanishes when  Advaitic wisdom dawns. When Advaitic wisdom dawns, then the Soul, the Self, remains in its own nondual awareness in the midst of the duality. : ~ Santthosh Kumaar