In this Upanishad the meaning of Omkaara or AUM, the different forms of Brahman and the theories of creation are discussed.
In this Upanishad AUM is identified with the fearless Brahman. It is also identified with the Lower Brahman and the Higher Brahman. AUM is the soundless sound, it is in the beginning, middle and end of all things, it is unrelated to any effect and is immutable. A person meditating on AUM as all pervading and immutable, is not affected by grief or sorrow and finally attains the Supreme reality.
The four states of consciousness are described in this Upanishad. Of the four three are ordinary states of consciousness. These are jagrti, svapna and susupti. Jagrti is the waking state, svapna is the dreaming state, susupti is the state of deep sleep. Turiya, the fourth state of consciousness, at once embodies and transcends these three states of consciousness. Turiya is the Transcendental Brahman. Turiya is Saccidananda – Existence, Consciousness, Delight. It is here, in turiya, that a highly advanced seeker or spiritual Master can actually hear the soundless sound, AUM, the supreme secret of the Creator.
The Mandukya Upanishad also tells us about the Universal Soul. The Universal Soul has two aspects: vaisvanara and virat. The microcosmic aspect is called vaisvanara; the macrocosmic aspect is called virat. Jagrti, vaisvanara and the letter ‘A’ from AUM form the first part of Reality. Svapna, the dreaming state; taijasa, the brilliant intellectual impressions; and the letter ‘U’ from AUM form the second part of Reality. Susupti, the state of deep sleep; prajna, the intuitive knowledge; and letter ‘M’ from AUM form the third part of Reality.
Using logic it is explained in the Upanishad that the objects perceived in both the waking and the dreaming state are illusory. As dreams, illusions and castles in the air are viewed, so is the tangible universe viewed by enlightened-ones. The idea of unreality, i.e. duality does not exist. They alone in this world are endowed with the Knowledge of the Supreme Reality who is firm in their conviction of the sameness and birthlessness of Atman.
It is also considered that the entire creation is the outcome of God’s will to create. This is well illustrated by the following verse:
The Lord Supreme, with His mind turned outward, imagines in diverse forms various objects either permanent, such as the earth, or impermanent, such as lightning, which are already in His mind in the form of vasanas, or desires. Again, He turns His mind within and imagines various ideas.