The Significance of OM
The Mandukya Upanishad explains OM:
It is a word but is also a sound or resonance. OM has three sounds known as ‘matras’ and consist of ‘A, U, M’. A + U combine to form ‘O’ and when ‘M’ is placed alongside ‘O’, we get ‘OM’. In normal communication, when a man opens his mouth to speak with naturally enunciate with the sound of ‘A’ and when he ends what he is uttering, and closes his mouth, we get the sound of ‘M’. When he brings his lips close to each other, and keeps his mouth half-open/half-closed, the natural sound that is heard is ‘U’. In short when one opens one’s mouth, we get the sound of ‘A’, when we close the mouth, we get the sound of ‘M’, and when it is midway, the sound of ‘U’ is produced. Therefore, the sounds of al languages, be they vowels or consonants, they are all contained in ‘OM’ – making it a unique, universal sound.
OM is also a symbol of Higher Consciousness or God or Paramatma. According to the Mandukya Upanishad, the state of ‘waking’ of the entire world is expressed by ‘A’ matra, the dream world is expressed by the ‘U’ matra, and the experience of deep sleep is expressed by ‘M’ matra. The entire universe is Paramatma himself and waking, dream, and deep sleep states form the entire universe. Since these three ‘matras’ are contained in OM – this becomes a wonderful symbol of God/Paramatma.
OM is also the symbol of the attribute-less Paramatma/God. The three above states get created from Brahman or Atman (Soul) and later merge back into it, similarly, OM comprising of the three ‘matras’ gets created from Silence or the absence of sound and later merges into it. That is why the silence between the two utterances of OM which is known as ‘amatra’ is the symbol of the attribute-less Brahman/Paramatma/God.
On stating OM, the ‘A’ matra merges into ‘U’, the ‘U’ matra merges into ‘M’, and the ‘M’ matra merges into silence. In the same way, during worship or meditation, while uttering OM as a support, a spiritual seeker merges the gross waking world into the subtle world, and the subtle world into the causal world. In time with progress, he transcends that too and abides in silence – the attribute less, peaceful, non-dual Self or I AM. This is the Ultimate state in worshipping or citing OM. OM indicates everything that is in existence – that which is the basis of entire existence and also that which is beyond all.
OM is also known as ‘pranava’ which means – that through which Paramatma/God is glorified. Why is OM chanted at the start of prayers or mantras?
It is believed that God/Paramatma started creating the universe after the utterance of ‘OM’ and ‘Atha’. Therefore OM is considered to be auspicious and should be stated before starting anything, which is why most mantras and Vedic prayers begin with ‘OM’. In OM, we can find the aim of life as well as the means to achieve that aim in the universe – with truth as it’s sub-stratum. To illustrate this further, OM is the bow, the individual self is the arrow, and the eternal Brahman/Paramatma is the target. Recitation of OM on a daily basis will allow one to become one with the target.