All mantras are based on the mythological Gods keeps one in the prison of the dualistic illusion.+

Why waste time discussing yoga, religion, worship of the religious Gods glorifying of the Gurus in the Atmic Path. 

Self-knowledge is not for those who believe in religion and its beliefs like mantras and worship of Gods.   Mantras and prayers are nothing to do with the Atmic path. Those who are attached to   Mantras and prayers and worship must continue in their chosen path the Atmic is not for those who are stuck with religious dross. In the Atmic path, the discussion is unimportant. One must think deeply and reflect on the subject. Passing their opinion with their accumulated knowledge will not help anyone.  

Mythology deals with symbols. It is not history; it is not concerned with objective reality. But that does not mean that it is not concerned with reality itself. It is concerned with subjective reality. These Gods, these mythological symbols, do not exist outside you, but they have a psychological existence and that psychological existence can be helpful, can be used. So the first thing to be understood is that they are not real persons in the world, but they are real symbols in the psyche of man.

Mythological Gods are a  myth. All mantras are based on the mythological Gods that keeps one in the prison of the dualistic illusion.   The mantras never help to cross the trash hold of the form, time, and space.  Mantras meant for the ignorant populace who believe the form, time, and space as reality.  What is the use of the mantras based on the false God that will yield false fruits?

That is why Sage Sankara says:~   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?

62. A disease does not leave off if one simply utters the name of the medicine, without taking it; (similarly) without direct realization one cannot be liberated by the mere utterance of the word Brahman.

That is why In 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.”

The people who follow religion think that following their inherited religion is their duty.  And questioning the Guru or scholars is irreligious.  Thus, they indulge in rituals and hearing of religious discourses.   They are weak and timid.

Lord Krishna says Ch ~V: ~ “Those who know the Self in truth.". The last two words (tattvataha) are usually ignored by pundits, but they make all the difference between the ordinary concept of God and the truth about God.

The dualistic worship of "God” is only for the ignorant populace. The God in truth is only Atman, the innermost Self.   In reality,  there is no duality, no differentiation. Only Atman exists.

The Vedas confirm God is Atman (Spirit), the Self.

Rig Veda: ~ The Atman is the cause; Atman is the support of all that exists in this universe. May ye never turn away from the Atman the innermost self. May ye never accept another God in place of the Atman nor worship other than the Atman?" (10:48, 5)

Rig-Veda 1-164-46 and Y.V 32-1 clearly mention that God is “One”.

Rig Veda declares God is ‘ONE’ and God is Atman, then why believe and worship in place of real God.

Brihad Upanishad: ~ “If you think there is another entity, whether man or God there is no truth."

When Upanishad itself declares: ~   Sarvam khalvidam brahma ~ all this (universe) is verily Brahman. By following back all of the relative appearances in the world, we eventually return to that from which it is all manifest – the non-dual reality (Chandogya Upanishad). 

Sage Sankara’s Supreme Brahman (God) is impersonal, Nirguna (without Gunas or attributes), Nirakara (formless), Nirvisesha (without special characteristics), immutable, eternal and Akarta (non-agent). It is above all needs and desires. It is always the Witnessing Subject. It can never become an object as it is beyond the reach of the senses. Brahman is non-dual, one without a second. It has no other beside it. It is destitute of difference, either external or internal. Brahman cannot be described because the description implies a distinction. Brahman cannot be distinguished from any other than It. In Brahman, there is not a distinction between substance and attribute. Sat-Chit-Ananda constitutes the very essence or Svarupa of Brahman, and not just Its attributes. The Nirguna Brahman of Sage Sankara is impersonal.

What happens if one worships which is not the real God with mantras and prayers based on the dummy gods.  It is only priest crafted baggage.

In Yajurveda says: ~ 

Translation 1.

They enter darkness, those who worship natural things (for example air, water, sun, moon, animals, fire, stone, etc).

They sink deeper in darkness those who worship sambhuti. (Sambhuti means created things, for example,  table, chair, idol, etc.) (Yajurveda 40:9)

Translation 2.

"Deep into the shade of blinding gloom fall asambhuti's worshippers. They sink to darkness deeper yet who on sambhuti is intent." (Yajurveda Samhita by Ralph T. H. Giffith pg 538)

All the accumulated knowledge of religion and yoga and paths and theories are mere dross in pursuit of truth. Religion and yoga are helpful for the populace, but they are a barricade in unfolding the mystery of the mind. Therefore, the orthodox people, if they are seeking the truth, then they have to drop all accumulated dross to acquire nondual wisdom.  Advaitic wisdom alone is a weapon to eliminate ignorance. :~Santthosh Kumaar