Holding any teacher or teaching or accepted truth as yardstick blocks the realization of ultimate truth of Brahman

A person perceives the world within the mind.  Absent of mind is absent of waking or dream. Thus waking or dream is mind.

One thinks he is an individual separate from the world within the mind. He is unaware of the fact that,  the mind is not within his brain, but he and his experience of the world are within the mind.  Thus, he thinks he is born in this world and world existed prior to him. Thus this conviction makes him believe the birth, life and death as reality.  Until this conviction is thee he will   views and judges the worldview on the physical base, which is the cause of ignorance of the fact that, the the formless  soul or consciousness is the innermost self.

This ignorance of the true self is the main hurdle in pursuit of truth. Therefore, it is very much necessary to rectify the seeking base from physical (form) to spirit (formless) before proceeding further in pursuit of truth.

If the seeking base is not rectified it will lead one towards hallucination. When the mind itself is myth then the man and his experience of the world is bound to be myth. Therefore perfect understanding of the mind will help one to unfold the mystery of the mind.  It is impossible to unfold the truth on the base of false self within the false experience, because the truth is prior to the appearance of the falsehood.  And falsehood creates ignorance.

Seeker has to drop all accumulated knowledge if he is serious about his pursuit of truth and start a fresh. Holding any teacher or teaching or accepted truth as yardstick blocks the realization of ultimate truth of Brahman.   Seeker has to burn down the ignorance by rectifying the  reasoning base  from form(ego)  to formless (soul)in order to acquire Self-knowledge or Brahma Gnana  or Atma Gnana.