The Upanishads declare :~ It is impossible to find and realize the truth via religion and scriptural studies.+

I quote scriptures to indicate that, the scriptures are also saying the same thing what I am saying. To realize the ultimate truth or Brahman no scriptures are needed. I am highlighting only the rational views of the sages of truth. 

People think that by studying Vedas one will be able to get Self-realization but it is not so.  Vedic studies lead to nowhere. What is the use of studying scriptures when Upanishads itself declares:-

Katha Upanishad:~   This Atman cannot be attained by the study of the Vedas, or by intelligence, nor 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)

                                                                                                                          

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

When the Upanishad says:  the human goal is to acquire Self-Knowledge and they indicate the personal gods, scriptures, worship, and rituals are not the means to Self –Knowledge, then why anyone should indulge in it.

The Upanishads declare:~

 
Mundaka Upanishad 1:2:8:~ “Remaining in the fold of ignorance and thinking “we are extremely wise and learned,” the fools with boastful nature ramble about like the blind led by the blind alone.” 

Mundaka Upanishad 3:2:3:~ “The weak and timid cannot realize the Self. Self-Realization is not possible through intellect or hearing the spiritual discourse. One who welcomes God in every activity, through a thorough controlled and disciplined life, to him also the Soul is revealed

Katha Upanishad 1:2:23:~ The Soul cannot be realized through hearing the scholarly explanation of the discourses, not even by the intellect.

Katha Upanishad 1:3:6:~“Through the knowledge of the Soul, God, one is pure and clean constantly.” Neither by reading the book nor by taking a bath at the holy place has one become pure. Inner purity is possible when one remains in constant touch with the Soul. Constant Soul Consciousness is real purity. 

Kena Upanishad 2:4:~ When it is known through every state of cognition, it is rightly known, for (by such knowledge) one attains life eternal. Through one's own 'Self' one gains power and through wisdom, one gains immortality. 

Kena Upanishad 2:5  If here one knows it, then there is no need to study Vedanta or any scriptures to self-realization.

Yoga Vasistha:~ "Teachers, interpretations of sacred texts, the force of religious merit--none of these lead to the realization of that Ultimate Truth which is revealed in the clear reflection of the heart, engendered from contact with the good."

Sage Sankara: ~ VC- Let erudite scholars quote all the scripture, let Gods be invoked through sacrifices, let elaborate rituals be performed, let personal Gods be propitiated---yet, without the realization of one‘s identity with the Self, there shall be no liberation for the individual, not even in the lifetimes of a hundred Brahmas put together (verses-6)

Sage Sankara said: ~ Talk as much philosophy as you like, worship as many Gods as you please, observe ceremonies, and sing devotional hymns, but the liberation will never come, even after a hundred aeons, without realizing the Oneness.

Sage Sankara:~ VC- 61. For one who has been bitten by the serpent of Ignorance, the only remedy is the knowledge of Brahman. Of what avail are the Vedas and (other) Scriptures, Mantras (sacred formulae), and medicines to such a one?

Upanishads: ~ 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. (Upanishads Nikilanada - Ch II-5 P-14)

The seeker has to overcome all the obstacles in pursuit of truth on his own. They are so many scholars who mastered philosophy. It is impossible to acquire Self-knowledge through Vedas and theoretical philosophy. Because their preaching is based on spirit and practices is based on ego or waking entity.

Katha Upanishad: ~ This Atman cannot be attained by the study of the Vedas, or by intelligence, nor 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)

It is very difficult to talk to people about the ultimate truth or Brahman because everyone thinks he knows the ultimate truth or Brahman. 

This- I know business is dangerous. And whatever his reached conclusion is second-hand stuff. Therefore, accepting accumulated knowledge without verification will lead the seekers to hallucinated realization based on the ego. One may have some flashes of truth when someone tries to indicate it through fewer words. But it takes nearer to the truth, not realization.

Upanishad says:~ "He who thinks he knows, does not know." This means that to know anything implies a second, an object of knowledge, hence duality, i.e. no Gnana.

Tripura Rahasya: ~ Second-hand knowledge of the Self-gathered from books or Gurus can never emancipate a man until its truth is rightly investigated and applied; only direct realization will do that. Realize yourself, turning the mind inward. ~ (18: 89)

The pursuit of truth is a mental journey. Deeper Self-search makes one aware of ‘what truth’ is and what is untruth’. When one gets a firm conviction of ‘what is the truth then the subconscious will reject the untruth. Whatever prevails after rejecting the untruth is the ultimate truth or Brahman.

Brihadaranyaka Upanishad says:~ In that unitive state there is neither father nor mother, neither worlds nor gods nor even the Scriptures. In that state, there is neither thief nor slayer, neither low caste nor high, neither monk nor ascetic. The Self is beyond good and evil, beyond all the suffering of the human heart.

Sage Sankara says ~ 58. Loud speech consisting of a shower of words, the skill in expounding the Scriptures, and likewise erudition - these merely bring on a little personal enjoyment to the scholar but are no good for Liberation.

59. The study of the Scriptures is useless so long as the highest Truth is unknown, and it is equally useless when the highest Truth has already been known.

60. The Scriptures consisting of many words are a dense forest that merely causes the mind to ramble. Hence men of wisdom should earnestly set about knowing the true nature of the Self.

The seeker has to without the scriptures move ahead in his pursuit of truth. 

The Soul is the innermost Self. The Soul is present in the form of consciousness. It is the consciousness that creates an illusion and it is the consciousness that gets free of it. The words may aggravate illusion; words may also help dispel it. There is a need to repeating the same truth again and again until it becomes reality.

The seeker has to reflect on the truth, which is beyond the form, time, and space constantly until he gets a firm conviction. People need hearing words of wisdom until facts speak to them louder than words, and if here one knows it not, there is a great loss. Hence, seeing the Real in all beings, wise men become immortal on departing from this world.

Scriptures are being added from time to time. This process will go on. There is the final authority among them? One contradicts the other: duality reigns supreme.

The Upanishads are Self-contradictory. Every pundit even gives conflicting interpretations of them. The final authority, therefore, is using one’s own reason. One should apply his reason to them.

The scriptures are for the ignorant masses, who wholly accept the material world as it presents itself. Gnana is for those who have begun to realize that things are not what they seem.

The Scriptures are of value only when dealing with persons who are incapable of understanding the truth. They have no value as authority for those who use reason. I quote only verified citations from the scriptures. I need no scriptures, but I quote them to help the seekers to realize it is possible to acquire Self-knowledge without the scriptures.  

The Upanishads are the only scriptures in the world that says:  It is impossible to find and realize the truth via religion and scriptural study.:~Santthosh Kumaar