The discipline of silence doesn't mean just taking a short vacation from the spoken word. It also means giving complete relaxation to the muscles, the tissues, the tongue itself. A modern writer once said: "Knowledge has never been known to enter the head via an open mouth." It is when you become completely silent that you are able to absorb knowledge. God speaks in silence. The discipline of silence is essential on the path.
That which saves society is not that which can be seen upon the surface of things. It is not the power of industry, of war, of genius, of letter or arts. It is what touches its depths in a silence called the silence of good things. -- From a NY Times interview