Sathya Sai Baba The World-Avatar Teaching and Revelations

Meditation on OM (pranava).
1. The best spiritual teaching is the sacred syllable OM which summarizes
many principles of theology, philosophy and mysticism.
(...)
OM is the primal sound inherent in the life-breath. Every time you
breathe, you say so'ham; 'so' when you inhale and 'ham' when you
exhale, meaning. “He-I” instilling into yourselves the conviction
that he who is all this external world is I who is all this internal
world, the conviction of unity, during deep sleep, when the senses,
the brain and the mind are dormant and functionalised, the “He”
and the “I” are not cognized as separate; the so (He) and the ham
(I) both fade and the sound so'ham is transformed into OM, indicating
the merger of the external with the internal into one truth. OM
has also many other significances and the meditation on the OM
is a valuable, for the seeker of reality. It is like the seven colours of
the sun's ray merging into one colourless (white) brilliance.
2. Aspirants would be benefited more if they repeat the sacred formula
(mantra) with the OM added in the beginning. When they
have proceeded some distance thus, they can give up even the
words and concentrate on the form depicted through the sound
and transform the mantra into the Godhead himself. That is why
the Sruthi says: “Brahman is silence, absence of sound”.
3. Constant repetition of OM and intense meditation on its meaning
are recommended for aspirants who seek cognition of the indwelling
Divine. Peace means peace and peace is invoked thrice, in
order to allay the three sources of sorrow; operating through the
individual organism, the deities and the cosmic intelligence.
4. OM is the bow; the Atman is the arrow; Brahman is the target. So
the aspirant must, like the practitioner of the art of archery, be unaffected
by things that agitate the mind. He should pay one-pointed
attention to the target; then the bowman is filled with the target;
he becomes the thing meditated on. In the Sruthis the OM is extolled
in various ways. Therefore this mantra which liberates man
can be recited and meditated upon by all, you need have no
doubts on this point.
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