The karma theory is based on the birth entity whereas the Soul, the Self is unborn eternal.+

The karma theory is based on the birth entity whereas the Soul, the Self is unborn eternal because it is the ever formless, timeless, and spaceless existence.

You are not the ‘Self’ because you are the birth entity. You are born, live, and die within the world, which is the dualistic illusion.   Whatever karma performed with the dualistic illusion is bound to be an illusion.

The karma theory based on the birth entity is a false theory. Realize the Self is not the birth entity but the Self is the unborn Soul, therefore, the unborn Soul has no karma because it is the ever formless timeless, and spaceless existence.

Religion is based on the birth entity, therefore, religion is based on falsehood, not truth. From the standpoint of the unborn, Soul the religion and its belief and its theories are falsehood based on the false self (birth entity)

There is nothing more rational, more intelligible, and more un-dogmatic insights of Sage  Sankara is to drop all the theistic non-duality or Advaita which is meant for those who are incapable and not receptive to realize the ultimate truth or Brahman.

People’s approach was more practical, and they are stuck with the belief of their inherited belief system.

Religions are based on belief, not the truth. Religions are more concerned with their beliefs dogmas and superstitions.

Religious Gods are based on imaginary beliefs. The beliefs are not the truth. The belief is part of the dualistic illusion.  The Atman is Brahman or God in actuality.   Other than the Atman God all else is an illusion.  Whatever is based on the belief is a myth.

Ish Upanishad declares: ~ “Those people who have neglected the attainment of Self-knowledge and have thus committed suicide. 

Those people who have neglected the attainment of Self-knowledge and have thus committed suicide, as it were, are doomed to enter those worlds after death. This is a condemnation of people who do not try to attain Self-knowledge. They are, in a real sense, committing suicide, for what can be worse than being a slave to sense enjoyment, completely oblivious of the real purpose of life, which is to be one's, own master?

Ish Upanishads: ~ Avidya is Karma and therefore a hindrance. (Mantra 10)

Sage Sankara: ~ “Action (karma) cannot destroy ignorance, for it is not in conflict with or opposed to ignorance. Knowledge does verily destroy ignorance as light destroys deep darkness. ~ Atma Bodha

Sage Goudpada says:~ the merciful Veda teaches Karma and Upasana to people of lower and middling intellect, while jnana is taught to those of higher intellect.

So they clearly indicate rituals and theories are not meant for the ignorant populace, not for those who are searching for higher knowledge or wisdom.   The path of wisdom is the only means to realize the truth, which is beyond form, time, and space.  

All the orthodox Advaitins indulge and immerse themselves in the ritualistic oriented lifestyle and follow the path of Karma and Upasana which is meant for lower and middling intellect and not for realizing the Advaitic truth.  Many chose these orthodox scholars as their gurus. But these gurus are good to learn the conceptual Advaita meant for those Orthodox who believe their conduct-oriented lifestyle leads to Moksha [liberation].  But religious-based Advaita is not the means to acquire Self~ knowledge or nondual wisdom.  Those who are seeking the truth have to do their own homework to acquire Self-knowledge or Brahma Gnana or Atma Gnana.

When everything is consciousness, where is the room to say the thinker, thought, words, body, and the universe are not the consciousness? The consciousness alone is real and eternal and the thinker, thoughts, words body, and the universe are merely an illusion created out of the consciousness.

Sage Sankara says in Aparoksh Anubhuti:~ 88. When the whole universe, movable and immovable, is known to be Atman, and thus the existence of everything else is negated, where is then any room to say that the body is Atman?

89. O enlightened one; pass your time always contemplating on Atman while you are experiencing all the results of Prarabdha; for it ill becomes you to feel distressed.

90. The theory one hears from the scripture, that Prarabdha does not lose its hold upon one even after the origination of the knowledge of Atman, is now being refuted.

91. After the origination of the knowledge of Reality, Prarabdha verily ceases to exist, since the body and the like become non-existent; just as a dream does not exist on waking.

92. That Karma which is done in a previous life is known as Prarabdha (which produces the present life). But such Karma cannot take the place of Prarabdha (for a man of knowledge), as he has no other birth (being free from ego).

93. Just as the body in a dream is superimposed (and therefore illusory), so is also this body. How could there be any birth of the superimposed (body), and in the absence of birth (of the body) where is the room for that (i.e., Prarabdha) at all?

94. The Vedanta texts declare ignorance to be verily the material (cause) of the phenomenal world just as the earth is of a jar. That (ignorance) being destroyed, where can the universe subsist?

95. Just as a person out of confusion perceives only the snake leaving aside the rope, so does an ignorant person see only the phenomenal world without knowing the reality?

96. The real nature of the rope being known, the appearance of the snake no longer persists; so the substratum being known, the phenomenal world disappears completely.

97. The body also being within the phenomenal world (and therefore unreal), how could Prarabdha exist? It is, therefore, for the understanding of the ignorant alone that the Shruti speaks of Prarabdha.

98. “And all the actions of a man perish when he realizes that (Atman) which is both the higher and the lower”. Here the clear use of the plural by the Shruti is to negate Prarabdha as well.

99. If the ignorant still arbitrarily maintain this, they will not only involve themselves in two absurdities but will also run the risk of forgoing the Vedantic conclusion. So one should accept those Shrutis alone from which proceeds true knowledge.

 The above proves that the karma theory is a reality only on the base of false Self (ego or you), where one thinks of the body and the universe as a reality. When one becomes aware of the fact that, the ‘Self ‘is the unborn  Soul then the karma theory becomes part and parcel of illusion.

Sage Sankara says: ~ From the point of any of these four uses karma is of no use for attaining liberation. Remaining in one's own true form is released. It consists of realizing the true nature of the Self which is ever-existent and eternal. Moksha, therefore, is not something to be produced, for it is eternal (nityatvat). It is not something to be purified, for it is bereft of all qualities and impurities (nirgunatvat, nirdoshatvat cha). There is also another reason here. It cannot be purified since it is not a means (asadhanadravyatmakatvat). Only a thing that serves as a means can be purified, as the sacrificial vessel or clarified butter by the sprinkling of water and so on. (commentary on Bhr, Upanishads 3-3-1)

Sage Sankara says:~ Karma is not competent to remove ignorance, for it is not opposed to it. It does not matter in what way we characterize ignorance, whether as the absence of knowledge or as doubt or as erroneous knowledge. It is always removable by knowledge, but not by action in any of its forms, for there is no contradiction between ignorance and karma. (Commentary on   Brah.3-3-1 )

Remember:~

Taittiriya Vartika, verse-24:~ There is also another reason for rejecting this view. Karma involves duality in the form of means and end, doer, and deed. The perception of duality is ignorance. Further, it is only a person who has the desire to perform karma. Since he is ignorant of the non-dual Self, he thinks that there are objects other than the Self which he should strive for and that there are persons for whom he should suffer in his body. "He struggles to desire something for himself, something else for his son, the third thing for his wife and so on and gets involved in the cycle of births and deaths." (Brh. Up. Sankara's Commentary, 4-4-12) 

In short, karma presupposes desire, involves duality, and is, therefore, a product of avidya. If so, how can it destroy avidya, the root cause of bondage, and thereby cause liberation? 

If one accepts the karma theory as a reality, he will never be able to come out of ignorance. And ignorance makes him believe the cycle of birth, life, and death or pain and pleasure as a reality.  Thu, s the freedom which one is seeking will remain a distant dream. For the one who accepts the experience of birth life, death, and the world as a reality, Self-knowledge is impossible.

Thus, the seeker of truth must know the fact that the body which is born, lives, and dies is not the Self. Since he is taking the body to be the Self, he is experiencing the duality as reality within the waking experience. : ~ Santthosh Kumaar