He (Shiva) is manifested first in the initial movement of that breath, which is only filled with life (pranamayah)
and then during breathing in and breathing out (prana),
which in exhaling, creates
and in inhaling, destroys.
In reality, this breath is residing in the heart of beings.
(Svacchanda T. 7.25)
The Life Force, Prana
In the teachings of Yoga we find a description of an encompassing, all pervading and all penetrating life force. In Sanskrit it is called prana and the term does not only denote life force but the act of breathing as well. Prana, inspite of its all penetrating nature is readily available to us primarily in the air we breathe and the food we eat.
According to the teachings of Yoga with the breathing and the food, gross as well as subtle substances are absorbed, distributed and circulated in the body in a huge network of pathways or channels (nadi).
We absorb lesser amounts of subtle energies along with our sense impressions as well. Aside from our intake of food, oxygen and sense impressions, subtle energies are derived from the impact of other natural elements of our environment on our organism. We derive prana whenever we come into contact with other living beings, the earth and vegetation as well as from the impact of energies like light and heat. Life energy is in constant movement, it contracts (sancocha) and expands (unmesha), it vibrates and pulsates (spanda). In the Philosophy of Yoga the most subtle form of life energy manifests as primal subtle sound and vibration (nada, dhvani), which is the origin of gross sounds, of speech, words (vac) and syllables (varna).
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