It is foolish to say I AM THAT, I AM THIS without realizing what the 'Self' is, and what 'Self 'is not.+

The Soul is the spiritual heart. The Soul is Self-evident. It is not established by extraneous proofs. It is not possible to deny the Soul because It is the very essence of the one who denies it. 

The spiritual heart is not within the physical body.  The Soul is the spiritual heart.  The world,  in which you exist is within the Soul, the spiritual heart.

 The ‘I’ is present in the form of the mind. The mind is present in the form of the universe.  The mind arises from the Soul as waking or dream (duality)  and subsides as deep sleep (nonduality).   Thus, the Soul is the source. Thinking the spiritual heart is within the body is erroneous because the Soul is the ever formless, timeless, and spaceless existence.  

The ‘Self’ is not within you.  The world, in which you exist, is within the Self.’You are bound by form, time, and space, whereas the Self is the formless, timeless, and spaceless existence.  You are the false self within the false experience.

No one can stay as Self without realizing the Self. After realizing the Self-nothing stays as reality other than the Soul, the innermost Self.  It is foolish to say I AM THAT, I AM THIS without realizing what the 'Self' is, and what 'Self 'is not.  

When you are the false self within the false experience, how can you say ‘I AM THAT’ when the ‘Self ‘is neither this nor that.  

The Self is the fullness of consciousness. Therefore, there is nothing apart from it Thus, any division (body, ego, and the world) within the consciousness is merely an illusion.   Thus, whatever is experienced as a person within the illusion is bound to be an illusion.

The nature of the soul, the innermost self is awareness. Only through Advaitic wisdom, the truth beyond the form, time, and space is revealed.

A perfect understanding of ‘what is what” is needed to realize the truth, which is beyond form, time, and space. Getting stuck to some teaching keeps one in the prison of hallucination.  

That is why Sage Sankara indicated: ~ 65. As a treasure hidden underground requires (for its extraction) competent instruction, excavation, the removal of stones and other such things lying above it and (finally) grasping, but never comes out by being (merely) called out by name, so the transparent Truth of the self, which is hidden by Maya and its effects, is to be attained through the instructions of a knower of Brahman, followed by reflection, meditation and so forth, but not through perverted arguments.

66. Therefore, the wise should, as in the case of disease and the like, personally strive by all the means in their power to be free from the bondage of the duality. 

Then there is no need for the scriptures, religion, and the idea of God.  One has to be more rational to realize the Advaitic truth, which is the ultimate truth or scientific truth.:~Santthosh Kumaar