Within Sanātana Dharma, ātman is spoken of as the innermost essence of a being, the true self that is distinct from body, mind, emotions, and ego. It is the unchanging core of pure awareness that persists through all states of experience, serving as the silent witness to thoughts, sensations, and feelings without itself being altered by them. Described as eternal and deathless, it is not touched by pleasure or pain, gain or loss. Many teachings characterize this self in terms of existence, consciousness, and bliss, indicating that its nature is fundamentally luminous and whole. Spiritual practice is therefore oriented toward realizing this ātman, recognizing one’s identity not with transient roles and conditions but with this abiding, inner consciousness.

Brahman, by contrast, is spoken of as the absolute and infinite reality that underlies and pervades all that exists. It is the unchanging ground of being, beyond name and form, beyond time and space, and beyond all limiting attributes. The scriptures describe Brahman as the source, sustainer, and ultimate goal of the universe, the immanent presence within all things and at the same time transcending all phenomena. It is pure consciousness without subject–object division, the ultimate reality in which all worlds, beings, and even the gods themselves have their origin and support. In many teachings, Brahman too is characterized as existence–consciousness–bliss, indicating that the deepest nature of reality is of the same quality as the deepest nature of the self.

The relationship between ātman and Brahman is treated as a central mystery and insight within the tradition. Upaniṣadic statements such as “ayam ātmā brahma” and “tat tvam asi” affirm that the true self and the ultimate reality are not two separate principles but, at the highest level, one and the same. In Advaita Vedānta, this is expressed as the non-dual identity of individual consciousness and universal consciousness, with apparent separation arising only through ignorance. Liberation, or mokṣa, is thus understood as the direct realization that the innermost self is not other than the absolute reality that pervades all. Other Vedāntic perspectives also affirm Brahman as supreme reality while interpreting the link between ātman and Brahman in different ways, yet all hold that understanding this relationship lies at the heart of the spiritual path.