Brahman - Wikipedia
So, the phrase "atman is Brahman" is saying, quite simply, that the individual . are Hindu Darsanas that do not accept that the Atman is the same as Brahman or to understand the relationship between Atman and consciousness is to make. However, it may be generally said that the relationship of Atman to Brahman is most significant in the Hinduism of the Upanishads (c. BC). This is perhaps. According to some Hindus this power is identified with the self (atman) while others regard it as distinct from the self.
Atman & Brahman
Within Mimamsa school, there was divergence of beliefs. The Upanishadic discussion of Atman, to them, was of secondary importance. Time and space are indivisible reality, but human mind prefers to divide them to comprehend past, present, future, relative place of other substances and beings, direction and its own coordinates in the universe. John Plott  states that the Nyaya scholars developed a theory of negation that far exceeds Hegel 's theory of negationwhile their epistemological theories refined to "know the knower" at least equals Aristotle's sophistication.
Nyaya methodology influenced all major schools of Hinduism. One, they went beyond holding it as "self evident" and offered rational proofs, consistent with their epistemology, in their debates with Buddhists, that "Atman exists".
It also states that soul is a real substance that can be inferred from certain signs, objectively perceivable attributes.
Further, they both consider self-knowledge as the means of liberation, freedom and bliss. The difference between Samkhya and Advaita is that Samkhya holds there are as many Atmans as there are beings, each distinct reality unto itself, and self-knowledge a state of Ipseity. In contrast, the monism theme of Advaita holds that there is one soul, and that the self of all beings are connected and unified with Brahman.
Samkhya asserts that each being's Atman is unique and different. Some earlier mentions of Atman in Yogasutra include verse 2.
These verses also set the purpose of all experience as a means to self-knowledge. The atman is not the body; the body is not eternal.
BBC - Religions - Hinduism: Hindu concepts
The body houses the atman until the body dies. Atman is immortal and eternal. Brahman is "world soul" or "cosmic soul. It is the life source of all that has been, is and will be throughout the entire cosmos. It is not an individual being - it is more like the primal ground or reality of all being and existence. So, the phrase "atman is Brahman" is saying, quite simply, that the individual soul is the world soul.
In other words, each individual soul - say, yours or mine - comes from and is made of the same reality as the world soul.
Brahman and Atman: That Art Thou | The Pluralism Project
There is no distinction between us, on the one hand, and the ultimate divine reality, on the other. This is an amazing concept! It basically means that in our deepest selves, we are divine.
All living things are divine in their deepest selves. Now, that divine self may be hidden or covered over by hatred, envy, fear or other negative things. But, it is there nonetheless and it is our "true" and "eternal" selves. Maybe you've heard people say hello, goodbye or greet people with the word "namaste" accompanied by clasped hands and a bow.