Tat Twam Asi—they are three simple words in Sanskrit. In simplicity lies much depth and meaning. That which you are looking for everywhere is you. It is within you and without two—though appearing a contradiction. The spiritual essence is there in the divine, present everywhere, and the same spiritual essence is in you. When this unity is understood, there is no difference between God and you, you and the world and the world and God. Everything is one alone.
This body made up of five elements—earth, water, fire, air and space—is caused by our thought patterns over eons of creation. It is a centre for experiencing what comes to us as good and bad due to our actions of the past. This is like maya or illusion because there is a changing pattern to it from beginning to end.
Sri Rama outlines to Lakshmana the different layers of the human being beginning with the gross body. The second layer is subtle and is composed of the mind, intellect and 10 sense organs—five of perception gathering inputs and five of actions sending the output. This is also a result of an inter-mixing of the five elements in its subtle form. This is the means by which the resident of this body goes through enjoyment and suffering constantly. This is a different body that is part of this gross body, say the wise people.
Deeper than this is a more subtle aspect which is the cause for this subtle mind and intellect. This deep part of the self is the cause for our individual existence in this world and this cause has no beginning. It can never be spelt out by the mind and intellect because, they are themselves effects of this cause. This innermost part of the being is an expression of the cosmic illusion called maya. It is a tool in the cosmic game and its own illusory nature makes itself appear different from the totality. Caught in its net of ignorance, we too believe ourselves to be different from the totality.
The self that you are seems covered by these layers as though a crystal appears with colours of the object placed near it. This self that you and I are has nothing to do with these different layers of causal, subtle and the gross bodies.
Even in the intellect, it appears as if there are three types of thought movements—in the waking, dream and deep sleep states. The three different characteristics of nature—Sattva or purity, Rajas or dynamism and Tamas or inertia—case these three different thought modifications in the intellect. They seem different from each other but all these three are like illusions in that same self which is eternal, supreme, Brahman that alone is as auspiciousness itself.