And how does one go chasing after a glimpse of the uncreated Light? The Hesychasts, high on Mount Athos, bowed their heads upon their breasts, took a deep breath, and plunged in. What they plunged into was prayer. It began with a tack with which to fix the attention. It became breath itself, an inlet for the universe to invade one's body until the entire cosmos, drawn in, heaved out, was transformed into prayer. The body's posture was important. The breathing was to be carefully controlled so as to keep time with the words. Eventually the prayer, breathed in, united with their very blood and heartbeat; breathed out, it blessed the world. And some monks claimed after a while to have indeed seen the Light of the Transfiguration, uncreated energy beheld by bodily eyes.
In any activity that requires concentrated effort, the breath quite naturally plays a role. If you have ever tried to thread a needle or repair a watch, you might have observed that without even thinking about it the breath quiets and deepens. Singers, swimmers, people who struggle with panic attacks, and a host of others learn the importance of proper breathing in order to negotiate the respective tasks at hand. Thus, that the art of contemplative practice can be facilitated by the breath should come as no surprise.