Sanatana Dharma–the Eternal Religion–is based on the direct experience of the sages of primeval India as well as the corroborating experiences of yogis throughout thousands of years. Originally all spiritual teachings were committed to memory, but in time they were written down to ensure their correct transmission. Simple as it is, Sanatana Dharma in its purity is found in twelve basic texts: the Isha, Kena, Katha, Prashna, Mundaka, Mandukya, Taittiriya, Aitareya, Chandogya, Brihadaranyaka, and Svetasvatara Upanishads, and the Bhagavad Gita. This last text is a digest and exposition of the upanishadic philosophy with emphasis on its practical application. Another book, the Yoga Sutras of Patanjali, presents the practical inner way to experience and manifest the truths of the upanishads and the Gita.

Although Om is to be found in each upanishad, at least as part of the opening and closing mantras of blessing, eight of them have sections dealing with Om Itself.

Brihadaranyaka Upanishad

“Om is Brahman, the Primeval Being. This is the Veda which the knowers of Brahman know; through it one knows what is to be known.” (Brihadaranyaka Upanishad 5.1.1) Om is Self-Revealing Divinity. It is the supreme “scripture” through which we come to know “what is to be known,” namely Brahman.

Chandogya Upanishad

“One should meditate on this Syllable [Om].” (Chandogya Upanishad 1.1.1) For, “That is the quintessence of the essences, the Supreme, the highest.” (Chandogya Upanishad 1.1.3)

“Speech [vak] and breath [prana] are joined together in the Syllable Om. Verily, whenever the pair come together, they fulfil each other’s desire. He who knowing this thus, meditates on the Syllable, becomes, verily, a fulfiller of desires.” (Chandogya Upanishad 1.1.6, 7) This is why Om is meditated upon by joining Its repetition to the breath, and why it is called the Pranava, the Breath Word.

The upanishad continues with the exposition of Om as the power of fulfillment, saying: “Verily, this Syllable is of assent, for whenever one assents to anything he says simply ‘Om.’ What is assent is fulfillment. He, who knowing this thus, meditates on the Syllable, becomes, verily, a fulfiller of desires.” (Chandogya Upanishad 1.1.8)

“Saying ‘Om,’ one recites: saying ‘Om,’ one orders: saying ‘Om,’ one sings aloud, in honor of that Syllable, with its greatness and its essence. He who knows this thus, and he who knows not, both perform with It. Knowledge and ignorance, however, are different. What, indeed, one performs with knowledge, faith, and meditation, that, indeed becomes more powerful. This, verily is the explanation of this Syllable.” (Chandogya Upanishad 1.1.9, 10)

A little later the upanishad returns to the power of Om to fulfil desires, saying: “He obtains wishes by singing [intoning], who knowing this, meditates on the udgitha [Om when it is part of Vedic recitation] as the syllable. This, with regard to the self.” (Chandogya Upanishad 1.2.14) That is, those who, desiring to know the Self, meditate upon Om will surely attain Self-knowledge.

“This sound is that syllable, the immortal, the fearless.…He who knows it thus, praises this Syllable, takes refuge in that Syllable, in the immortal, fearless sound, and having entered it, he becomes immortal.” (Chandogya Upanishad 1.4.4, 5) Om is the secret of immortality.

The upanishadic sages had much to say about the sun as the source of life, teaching that all sentient beings have come into the physical plane through the sun which is a gateway to the astral realms. To them the sun was not a ball of flaming gases (this is also the speculation of some astronomers) but a sphere of concentrated life forces. The souls that have evolved beyond the need for earthly experience pass back through the sun to higher worlds. Even more, the sages identified it with Om, saying: “Now, verily, what is the udgitha is the Om. What is Om is the udgitha. And so verily, the udgitha is the yonder sun and the Om, for the sun is continually sounding ‘Om.’” (Chandogya Upanishad 1.5.1) Scientists have only recently discovered this phenomenon. On page sixteen of the July 2004 issue of National Geographic we find this: “Bubbles the size of Texas cover the sun’s face…. Called granules, the short-lived cells of plasma carry heat to the surface through convection, the same way water boils in a pot. The rise and fall of granules creates sound waves, which cause the sun to throb like a drum every five minutes.”

“One should meditate on the breath in the mouth as the udgitha, for it is continually sounding ‘Om.’” (Chandogya Upanishad 1.5.3) Since our soul is always breathing Om, by intoning Om in time with the breath we put ourselves in tune with the very wellspring of our existence, linking up with our inmost consciousness.

“Now, verily, what is the udgitha is the Pranava. What is Pranava is the udgitha. [If one knows this], verily, from the seat of the hotri priest, all wrong singing is corrected, yea is corrected.” (Chandogya Upanishad 1.5.5) Negative karma is a major concern of those who seek liberation, for it ties us to the wheel of constant birth and death. Symbolically speaking, we “sing” our life’s directions as does the hotri priest, and often make mistakes. But through Om, “all wrong singing is corrected, yea is corrected.”

“This is the udgitha [Om], highest and best. This is endless. He who, knowing this, mediates on udgitha, the highest and best, becomes the highest and best and obtains the highest and best worlds. When Atidhanvan Shunaka taught this udgitha to Udara Shandilya, he also said: ‘As long as they shall know this udgitha among your descendants, so long their life in this world will be the highest and best.’ And so will their state in that other world be. One who thus knows and meditates–his life in this world becomes the highest and best, and so his state in that other world, yea, in that other world.’” (Chandogya Upanishad 1.9.2-4) Om glorifies both this life and the life beyond.

“As all leaves are held together by the stalk, so is all speech held together by Om. Verily, the Syllable Om is all this, yea, the Syllable Om is all this.” (Chandogya Upanishad 2.23.3) Om is every aspect of life itself. Speech, vak, is the essence of life. Therefore in grave illness and at the time of death the power of speech usually fails. As milk becomes diluted in water, so the consciousness of the departing soul becomes dispersed and wanders, confused. But this is not so for those who cling even in death to the repetition of Om.

Speaking of the final exit of the soul from the body, the upanishad says: “Even as a great extending highway runs between two villages, this one and that yonder, even so the rays of the sun go to both these worlds, this one and that yonder. They start from the yonder sun and enter into the nadis. They start from the nadis and enter into the yonder sun.…When a man departs from this body, then he goes upwards by these very rays or he goes up with the thought of Om. As his mind is failing, he goes to the sun. That, verily, is the gateway of the world, an entering in for the knowers, a shutting out for the non-knowers.” (Chandogya Upanishad 8.6.2,5)

Katha Upanishad

In the Katha Upanishad we find profoundest teachings on the true Self and its destiny. The inquirer asks to be taught the Transcendent Reality. The answer he receives is this: “I will tell you briefly of that Goal which all the Vedas with one voice propound, which all the austerities speak of, and wishing for Which people practice discipline: It is Om.” (Katha Upanishad 1.2.15) To be very colloquial: Om is IT.

Though absolute Unity, God is seemingly dual: transcendent and immanent, with form and without form, with qualities and without qualities, “higher” and “lower” Brahman. So the upanishad says: “Om, indeed, is the Lower Brahman; this is, indeed, the Higher Brahman. Anyone who, meditating on Om, wishes either of the Two [aspects], by him that is attained.” (Katha Upanishad 1.2.16) Om is both transcendent and immanent. In whichever plane we wish to abide, Om is the basis, the illuminator, the key to comprehension and mastery. Furthermore, we can meditate on God with Form (Saguna Brahman) and God without Form (Nirguna Brahman), God with attributes and God beyond attributes, with a single mantra: Om.

Logically, then, the upanishad concludes: “This [Om] is the best means [of attainment and realization]; this means is the Higher and Lesser Brahman. Meditating on Om, one becomes worthy of worship in the world of Brahman.” (Katha Upanishad 1.2.17) Om is that which transforms us, elevating our consciousness to the realm of the Divine and establishing it therein.

Mandukya Upanishad

“Om: this Syllable is all this. All that is past, the present and the future, all this is only the Syllable Om. And whatever else there is beyond the threefold time, that too is only the Syllable Om.” (Mandukya Upanishad 1) From the original Sound, Om, all things have come into manifestation as Its extension-embodiments. Everything that has ever existed, now exists, or shall exist, is the expansion of Om. Om is all-embracing Eternity, containing and transcending past, present, and future. There is nothing but Om.

That being true, the upanishad then says: “The Self [atman] is of the nature of the Syllable Om.…Thus the Syllable Om is the very Self. He who knows It thus enters the Self [Supreme Spirit] with his self [individual spirit].” (Mandukya Upanishad 8, 12) By means of Om, the eternal wave merges into the eternal Sea.

Mundaka Upanishad

The Mundaka Upanishad speaks further on meditation.

“Taking as the bow the great weapon of the Upanishads [Om], one should place in It the arrow sharpened by meditation. Drawing It with a mind engaged in the contemplation of That [Brahman], O beloved, know that Imperishable Brahman as the target.” (Mundaka Upanishad 2.2.3) The power of Om is emphasized by calling it a great weapon. Its intent and effect are serious and mighty–nothing less than union with the Absolute. It is called “the great weapon of the Upanishads” to indicate that Om, and Om alone, is the effective means recommended by the scriptures of Eternal Dharma for the realization of God. The japa and meditation of Om impel the consciousness of the yogi toward the Goal: Brahman. Moreover, it is the meditation of Om that “sharpens” the consciousness and renders it capable of union with Brahman.

“The Syllable Om is the bow: one’s self, indeed, is the arrow. Brahman is spoken of as the target of that. It is to be hit without making a mistake. Thus one becomes united with it [Brahman] as the arrow becomes one with the target.” (Mundaka Upanishad 2.2.4) It is Om that ensures we will unerringly (“without a mistake”) reach the Goal.

“He in Whom the sky, the earth, and the interspace are woven, as also the mind along with all the pranas, know Him alone as the one Self. Dismiss other utterances. This [Om] is the bridge to immortality.” (Mundaka Upanishad 2.2.5) The “He” in this verse is Om Itself, which is Brahman. It is the one Self. To drive the point home that Om is the sole means of uniting with Brahman, the upanishad says absolutely and flat-footedly: Dismiss other utterances–all other japa mantras. Why? Because only Om is the way to immortality.

Therefore, “Meditate on Om as the Self. May you be successful in crossing over to the farther shore of darkness.” (Mundaka Upanishad 2.2.6)

Prashna Upanishad

Living in the world of gadgetry, from mousetraps to atom bombs, one of the most frequent questions we (reasonably) ask is, “Does it work?” According to the Prashna Upanishad, “Satyakama, son of Shibi, asked [the Rishi Pippalada]: ‘Venerable Sir, what world does he who meditates on Om until the end of his life, win by That?’ To him, he said: ‘That which is the sound Om, O Satyakama, is verily the higher and the lower Brahman. Therefore, with this support alone does the wise man reach the one or the other.’…If he meditates on the Supreme Being [Parampurusha] with the Syllable Om, he becomes one with the Light, the Sun. He is led to the world of Brahman. He sees the Person that dwells in the body, Who is higher than the highest life.…That the wise one attains, even by the mere sound Om as support, That Which is tranquil, unaging, immortal, fearless, and supreme.” (Prashna Upanishad 5:1,2,5,7)

Om does it all.

Svetasvatara Upanishad

“Om is the Supreme Brahman, and in It are the Triad. [Commentators consider that “the Triad” means the individual soul, the cosmos, and the Cosmic Soul, Parameshwara.] It is the firm support, the imperishable. The knowers of Brahman by knowing what is therein [in the all-containing Om] become merged in Brahman, intent thereon [i.e., on Om] and freed from birth.” (Svetasvatara Upanishad 1:7) Om unites us with God and frees us from rebirth.

“As the form of fire when latent in its source is not seen and yet its seed is not destroyed, but may be seized again and again in its source by means of the drill [a pointed stick whirled to produce fire for the Vedic sacrifices], so it is in both cases. The Self has to be seized in the body by means of the Syllable Om. By making one’s body the lower friction stick and the Syllable Om the upper friction stick, by practicing the friction of meditation one may see the hidden God, as it were.” (Svetasvatara Upanishad 1:13,14) Here we see a hint of the practice of integrating our intonations of Om with the breath while centering our awareness in the Chidakasha area of the brain. It also points out that the japa and meditation of Om are not confined to our “spiritual” makeup, but affects our whole being, including the body.

“The knower of the real nature of Brahman that is identical with the Pranava, after keeping his body erect, by holding the three parts [the chest, the neck, and the head] in an upright posture, placing all the organs of perception and action along with the mind in his heart, should cross all the formidable streams [of samsara] with the ferryboat of the Pranava.” (Svetasvatara Upanishad 2:8) “Heart” in this verse means the Self, the core of our being, rather than the physical heart or the “heart chakra.” The idea is that through meditating on Om all the “streams” or faculties of our mind become merged in the consciousness of the Self.

This is perfect enlightenment, so the upanishad also says: “God is the Syllable Om, out of Him proceeds the Supreme Knowledge.” (Svetasvatara Upanishad 4:17)

Taittiriya Upanishad

“Om is Brahman. Om is all this. He who utters Om with the intention ‘I shall attain Brahman’ does verily attain Brahman.” (Taittiriya Upanishad 1.8.1) How glorious is Om! It is the Power of Enlightenment.

Bhagavad Gita

The supreme sage, Vyasa, in order to give us a complete picture of the upanishadic wisdom as well as the way to apply it in our life so we may attain the same vision of the sages who authored them, wrote the Bhagavad Gita based on the instructions given by Krishna to Arjuna on the eve of the Great Indian (Mahabharata) War on the battlefield of Kurukshetra. Om is a central element in Krishna’s exposition of spiritual life and practice.

Speaking from his perspective as the Infinite Being, enumerating his major manifestation-embodiments, Krishna says: “I am the syllable Om.” (Bhagavad Gita 7:8) “I am…the sacred monosyllable.” (Bhagavad Gita 9:17) “Among words I am the monosyllable Om.” (Bhagavad Gita 10:25) The meaning is that Om is not a symbol of God, It is God.

What to “do” with Om is then outlined by Krishna: “Engaged in the practice of concentration, uttering the monosyllable Om—the Brahman—remembering Me always, he…attains to the supreme goal. I am easily attainable by that ever-steadfast Yogi who constantly and daily remembers Me.” (Bhagavad Gita 8:12-14)

Yoga Sutras of Patanjali

The Yoga Darshan (Yoga Sutras) of Patanjali is the prime authority on yoga outside the Upanishads and Bhagavad Gita. Here are its words on God and yoga:

“Ishwara [God] is a particular Purusha [Spirit, Person] Who is untouched by the afflictions of life, actions, and the results and impressions produced by these actions. In Him is the highest limit of omniscience. [“In Him becomes infinite that all-knowingness which in others is only a germ”–Swami Vivekananda’s translation of the Yoga Sutras.] Being unconditioned by time He is teacher even of the ancients. His designator [vachaka] is the Pranava [Om]. [“His manifesting word is Om”–Swami Vivekananda.] Its japa and meditation is the way [or: should be done]. From it result [come] the disappearance of obstacles and the turning inward of consciousness. Disease, languor, doubt, carelessness, laziness, worldly-mindedness, delusion, non-achievement of a stage, instability, these cause the distraction of the mind and they are the obstacles. [Mental] pain, despair, nervousness, and agitation are the symptoms of a distracted condition of mind. For removing these obstacles [there should be] the constant practice of the one principle [the japa and bhavanam of Om].” (Yoga Sutras of Patanjali 1:24-32)

That completes the picture. We need only heed the instruction: “Having known what is said in the ordinance of the scriptures, you should act here in this world.” (Bhagavad Gita 16:24)