KathaUpanishad

avīmi te = I tell you;
saṅgraheṇa = in brief;
tat = that goal;
om iti etat = OM it is.
Yama said: The goal which all the Vedas declare, which all austerities aim at and
which men desire when they lead the life of continence, I will tell you briefly: it is
Om.
The Concept of AUM:
In the Mandukya Upanishad, we find, “AUM stands for the Supreme Reality. It is a
symbol for what was, what is, and what shall be. AUM represents also what lies beyond
past, present and future.” So we learn that it is all encompassing. In fact, “Om” also
represents Brahman, which is equated with the Self as we learn “Brahman is all, and
the Self is Brahman. This Self has four states of consciousness.” In the same
Upanishad, we find an explanation of these four states, as the four components of “om”.
The first sound is “a”, and is called “Vaishvanara” (where one is focused on the
external), and the second is “u”, is called “Taijasa”, (the dreaming state where one is
focused internal). The third is “m”, called “Prajna”, (the all-knowing state of deep sleep,
“in which one neither dreams nor desires”) and the fourth is called “Turiya”, (the
superconscious state which is “neither inward nor outward”). This final state also
represents the first three syllables, “A, U, and M”. “Om” is found in several places in the
Upanishads. For example, in the Amritabindu Upanishad, it reads, “keep repeating the
ancient mantra Om until it reverberates in your heart.”
(The Upanishads, by Eknath Easwaran, Mandukya Upanishad p.60, v. 1-8;
Amritabindu Upanishad p. 243 v. 7)
If you look at the Hindu symbolism today, the one that is associated uniquely is the
sound of Om and the symbol of Om. You may not find this symbolism of AUM as
common as the Devanagari Script AUM which came into existence much later in
history.
Yet the oldest AUM was in Tamil as given on the top left side. But the surprising thing
about it is that AUM is not found in any of the Vedas.
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