The Word That is God

means for the attainment of Brahman.” (Shankara, Commentary on the Mandukya Upanishad)
“When the syllable Om is known, one should not think of anything whatsoever, serving any
seen or unseen purpose; for he has got all his desires fulfilled.
“One should concentrate the mind on Om, Which is essentially the supreme Reality, for
Om is Brahman beyond fear, because for one who is ever fixed in It, there can be no fear
anywhere, in accordance with the Vedic text, ‘The enlightened man is not afraid of anything.’ 79
“Om is both the higher and the lesser Brahman. When the letters disappear [in the state
of meditation], Om becomes verily the supreme Self that is Brahman. …The idea implied is
that It is coextensive with all that is inside or outside; It is birthless; and It is a mass of
Consciousness, homogeneous like a lump of salt. Om is the origination, continuance, and
dissolution of all–of the whole phenomenal universe. …In this way indeed, having known Om
that is the Self, one attains identity with the Self at that very moment.
“One should know Om as God existing in the heart of all living beings. Having meditated
on the all-pervasive Om, that is the Self beyond the worldly state, the intelligent man does not
grieve, for no cause of grief can be possible then, in accordance with such Vedic tests as, ‘The
knower of the Self transcends sorrow.’
“Om being beyond measures is Turiya, It has infinite dimension and Its extent cannot be
determined. It is auspicious and holy because of the negation of all duality. He who knows Om
is a sage because of his meditating on the Supreme Reality, and not any other man, though he
may be learned in the scriptures.” (Shankara, Commentary on the Mandukya Karika)
“As the supreme Brahman cannot be directly indicated by words, etc., and is devoid of all
distinctions created by attributes–and as It is on that account beyond the senses–therefore
the mind cannot explore It. But to those who meditate on Om, Which is comparable to the
images of Vishnu and others, and on which is fixed the idea of Brahman with devotion, that
Brahman becomes favorable and reveals Itself. This is understood on the authority of scriptures.
Similar is the case with the Lesser Brahman. Hence it is said in a secondary sense that that
Brahman Which is both Lesser and Higher is but Om. Therefore one who knows this attains
either of the two [Brahmans] through this Om alone; only through this, that is a means for the
attainment of the Self, consisting in meditation on Om; for Om is the nearest symbol of
Brahman. The One is reached with the aid of Om, Which is a vehicle of advance.” (Shankara,
Commentary on the Prashna Upanishad)
“By means of the boat of Om that is Brahman one crosses over [samsara, the ocean of
birth and death]. The idea is that by controlling the senses through Om the enlightened
person should cross over the currents of the river of transmigration with the help of that Om.”
(Shankara, Commentary on the Svetasvatara Upanishad)
“One should contemplate in one’s mind, that is, meditate, that Om, as a word, is Brahman.
For ‘Om is all this.’ All that consists of sound is Om, since everything is permeated by Om in
accordance with another Vedic text: ‘As by the fibers the leaves are pervaded, so by Om is
pervaded all speech.’ 80 And since all that is nameable is dependent on the names, it is said that
79 Taittiriya Upanishad 2.9
80 Chandogya Upanishad 2.23.3
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