There is no need to study scriptures, or indulge in god and guru glorification or performing religious rituals in order to acquire Self-knowledge or Brahma Gnana or Atma Gnana.

Katha Upanishad says:

Fools dwelling in darkness, but thinking themselves wise and erudite, go round and round, by various tortuous paths, like the blind led by the blind. [Ch II-5 P-14 -Upanishads Nikhilananda]

It indicates that the one who is ignorant [darkness] of the true self [formless witness/Atman] searches truth by accumulating knowledge of every path and practice and uncertain about the truth, and thinks every path leads towards reality. The ignorance of the true self leads one towards unreality or hallucination.

 This Atman cannot be attained by the study of the Vedas, or by intelligence, or by much hearing of sacred books. It is attained by him alone whom It chooses. To such a one Atman reveals Its own form. [Katha Upanishad Ch-II -23-P-20]

This Atman cannot be attained through study of the Vedas, nor through intelligence, nor through much learning. He who chooses Atman—by him alone is Atman attained. It is Atman that reveals to the seeker Its true nature. [    3 –page-70 Mundaka Upanishad  Upanishads by Nikilanada]

The above passages further proves that: self-knowledge cannot be attained by study of the Vedas and intellectual understanding or by bookish knowledge.  Therefore there is no use of studying the Vedas and other scriptures in order to acquire the non-dual wisdom.  That is why Buddha rejected the scriptures, and even Sri, Sankara indicated that, the truth lies beyond religion, concept of god and scriptures.  

For the same reason Raman Maharshi said fortunate are the one who do not lose themselves in the labyrinths of philosophy. Bhagwan says: Take Vedanta, for instance: it speaks of 15 pranas the names and functions of it   which the student is asked to commit memory. Will it not be sufficient if he thought only one prana does the whole work of maintaining the body? Again the antakaran is said to think, to desire, to will, to reason etc. Why all these details? Has anyone seen antakarana, or all these pranas? Do they really exist? They are conceptual divisions invented by teachers of philosophy by their excessive analysis. Where do all these concepts end? Why should confusion created and then explained away? Fortunate is the man who does not lose him self in the labyrinths of philosophy, but goes straight to the source from which they all arise. (GURU RAMANA .By S.S Cohen -vii Danger of philosophy-Page -58-59)

Raman Mahrshi further explains [in page 111/112- practical guide to know your self]:-

Q: D: Is it not necessary to study the Vedas or at least Prastnatraya[Bagvad gita.Dasoponishad and Brahma Sutra all with commentaries] to ensure firm reazation?

A: Bhagvan: - No. Do you need all that to see yourself? All that is intellectual wealth, useful in explain doubts and difficulties if others rise them if you yourself encounter them in course of thinking. But to attain realization, all that is not necessary. You want fresh water to drink, but you do not require all the water of the river Ganges to quench your quest.

They alone in this world are endowed with the highest wisdom who are firm in their conviction of the sameness and birthlessness of Atman. The ordinary man does not understand their way. [Chapter IV — Alatasanti Prakarana 95-P-188 in Upanishads by Nikilanada]

This passage indicates the fact that everything is Atman/spirit. The one who views and judges the worldview on the base of his birth /body will not realize the fact that, the man including the world is created sustained and finally dissolves as Atman. Thus Atman alone is, and all else is mirage.

Thus self-knowledge is the aim of every human being. Since everyone thinks the physical body is the self their aim is misdirected and they focus their attention on materiality which makes one feel the duality [waking] as reality.

Nisagadutta said:  Millions are in search of the ultimate truth, and only one in million will be able to grasp and realize it. By focusing more attention on Atman by talking, writing, discussing only of Atman, the conviction grows and becomes firmer and the duality will fade away as reality. Atman/spirit which is one’s   true identity will prevail as birth-less and deathless, eternal substance and witness of the mirage called duality.

Therefore There is no need to study scriptures, or indulge in god and guru glorification or performing religious rituals in order to acquire Self-knowledge or Brahma Gnana or Atma Gnana.  Since, they are not the means to acquire non-dual wisdom. It is only waste of time and effort to indulge in those things.