OM – THE SOUND AND SYMBOL
Whole existence is reverberation – vibration of energy. When there is vibration there will be sound. Where there is vibration and sound there will be creation. Om is the fundamental sound of the relative reality (creation). It is the basic sound of this creation. All the other sounds are the manifestation of Om.
Om is the combination of three basic sounds A + U + M. All the other sounds are the mixing of these three basic sounds using the tongue. If you notice we can pronounce Om or A, U, M without the use of tongue (we can pronounce by using only the lip movement).
In the Vedas almost all the mantras start with Om. Om is used in karma kanda widely. In Vedanta it is mainly used for meditation. It is used to represent saguna Brahman as well as nirguna Brahman. Om is the basic vibration of this universe. It is the divine sound, symbol and mantra. It is the beej mantra for universal Consciousness. More than a japa mantra Om is used extensively for meditation. Since Om is the basic vibration of the universe when we meditate on Om we can easily connect with the Universe. Mandukya upanishad explains a unique technique for meditation on Om.
Human existence is based on three states (avastas). They are the waking, dream and deep sleep states. These states exist in Consciousness, which is known as Turiya. Turiya cannot be said as the fourth state. It is the underlying state. All the experiences exist in Turiya. We are able to experience the three states because of Turiya. Turiya can also be said as prapanjopashama, where all the other experiences of the universe disappear. Turiya is that state where all the other three states merge and reappear.
Three states (avastas)
In the waking state (jagrad avasta) we come in contact with the gross universe with our body, senses and mind. The Consciousness or Turiya in association with the body, senses and mind experiences the universe in the waking state. In other words, the Consciousness (Turiya) appears as the waking experience.
In the dream state (swapna avasta) we come in contact with the world of impression in the mind in sleep. The Consciousness or Turiya in association with the projection of the mind is the dreaming experience. In other words, the Consciousness (Turiya) appears as the dream experience.
In the deep sleep state (sushupti avasta), there is no internal world or external world. It is experience of darkness or ignorance. The Consciousness in association with the non-functioning of the mind is the deep sleeping experience. In other words, the Consciousness (Turiya) appears as the deep sleep experience.
That Consciousness (Turiya) is expressed as Om. Om is the symbol of Consciousness. All the three states appear and disappear in Turiya. Turiya is not a mystical experience; it is the fundamental nature of man.
Meditation on Om
Now, the three base sounds in Om are taken for meditation. Only for meditation Om is split as A, U, M (as its base sound). For chanting and mantra japa it should be pronounced as Om. According to the sandhi rules of sanskrit, when you combine A + U we get only O
(that is A + U = O), but when we meditate we split by its base sound.
All the waking experiences are identified with A
All the dream experiences are identified with U
All the deep sleep experiences are identified with M
When we meditate on Om we must bring in to mind this knowledge. All the waking, dream and deep sleep experiences appear and disappear in Consciousness or Om. There is a small gap between finishing and starting of the next Om. That gap is silence. That silence represents Consciousness or Turiya. So all the experiences appear, disappear and merge in Consciousness and again the same process.
Thus meditation on Om is explained in Mandukya upanishad. There are no experiences without Turiya. We are not aware of Turiya. To bring one to that deep pure Consciousness is meditation on Om.