I'm spending 4 days on a contemplative faculty retreat. Thirty three of us gathered together to be mindfully, attentive and intentionally silent. One of the three people leading the retreat spoke briefly about the purpose of the silence. She urged us to practice "noble silence" - a Buddhist practice of stilling not only the voice, but even our body language, a silence that lets one be alone in the midst, supported by the silence of others.
The monastic practices of "custody of the eyes" and the Great Silence serve similar purposes. To encourage us to hear rather than talk, with all our senses. To reverence the needs of others over our own. To be still, even in motion.