Ritual

The very sound of a mantra or a combination of them has the
capacity to arouse the divine forms or their energies. Each divinity
possesses a bija mantra, or seed syllable, which is its equivalent.
Thus the bija mantra is the root vibration or atomized form of
sound representing the essential nature of divinity.
The monosyllabic bija mantra is to tantric sadhana what a seed is
to a tree: just as the seed possesses the potential of the tree, in the
same way a single sound can contain the sum-total of divinity in its
vibration. The term bijakshara, 'seed syllable', consists of two
words: bija, meaning seed or germ, and akshara, which connotes
both 'syllable' and 'imperishable'. The true bijakshara ends within
an anusvara, or upturned semicircle with a dot in its centre, and in
romanized transliteration the anusvara is indicated with a dot
above or below the letter m. The anusvara is described as a
continuous nasal sound without any modification and is an
adaptation of an 'unpronounceable vibration'. The dot in the
anusvara represents the bindu, and is the visible form of Siva-Sakti.
Hans-Ulrich Rieker has made an illuminating observation:
Period (dot). It does not stand like a tombstone at the end of a Sanskrit
sentence, but is the sign for vocal vivification. The dot above the
consonant (which is always connected with a vowel) changes a dull ka
into a rich kam or kang, a ta into tarn or tang, pa into pam, and so on,
through all the consonants. It adds vibration to the dull sound. It is
especially significant that it raises O from the chest vibration to the Om
sound in the head, the higher sphere. Thus it raises the physical sound to
the chakra of consciousness, the ajna chakra between the eyebrows, and
gives it meaning. In this way, the dot becomes the symbol for sense. 31
The seed mantra is considered to contain the entire potentiality of
full significance of a doctrine. A treatise running to several
thousand verses, for instance, may be condensed into few stanzas,
and then summarized into a few lines, and finally abbreviated to a
bija mantra which, though the smallest sound unit, will still retain
the full power of the doctrine. The manifested bija mantra creates
cerebral vibration, and it is believed that even after the repetition of
a seed mantra has ceased, its effect continues. It is further held that
the power a particular bija mantra generates can be stored up in the
cerebral centre and activated at will.
Om, the most powerful of all sounds, is the source of all mantras
and a key to realization. It is made up of three sounds, a, u, m,
which symbolically represent the three ultimate tendencies or
gunas - creation, preservation, dissolution - and encompass all the
knowledge of the different planes of the universe. It is referred to as
the 'quintessence of the entire cosmos', 'monarch of all sounded The seed-syllable Om.
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