Breath in Meditation

Every meditation practice I have experienced (Tibetan Buddhist, Zen, Western Mysteries, Hindu, New Age, Vipassana etc.) there is certainly in the least a phase of the meditation dedicated to one's own breath.  In some cases, the entirety of the meditation might be on the breath, in other cases, it might be a preliminary to another meditation - but it's always there.

Bhante Gunaratana speaks to why the breath is a useful tool in meditation:

Breathing is a non-conceptual process, a thing that can be experienced directly without a need for thought. Furthermore, it is a very living process, an aspect of life that is in constant change. 

The breath moves in cycles--inhalation, exhalation, breathing in and breathing out. Thus it is miniature model of life itself.

 In Hinduism, the breath is referenced in: Bhagavad Gita, IV:29.  In this passage it speaks of offering the outgoing breath into the inhaling breath and so forth.  Paramhansa spoke often of the breath.  In his teachings the breath itself was a way in which to make spiritual progress.  He referred to a state of breathlessness... which was an equalibrium of breath.  It wasn't a state of "holding" or "restraining" one's breath - but a natural cessation of breath.  There's more on this perspective at: http://www.ananda.org/meditation/free-meditation-support/articles/go-deeper-into-meditation/

I remember meditating one time, when I was studying some works by a Zen teacher.  In my meditation my mind was wondering and I heard a television program my son was watching... it was distracting but I heard these words from the show: "What a noisy gate."

I came to accept that as a truth.  My mind was noisy.  The gate, is like an aspect of the mind.  It observes itself and all the thought activity going in and out of the gate.  Likewise, the gate is also like the breath... moving in and out.  When the breath is subtle - barely moving, then the gate is fixed - i.e. no noise.