It is in silence that the first signs of the life of prayer reveal themselves. The Spirit of God does not force Himself upon us. He is gentle as a dove. When the Lord told Moses that He would appear to him we read that He was not in the wind, nor in the earthquake, nor in the fire. But He spoke with Moses in a still, small voice.
We cannot hear that voice unless we become still, and for the one beginning in prayer, we cannot easily become still, if at all, unless we seek that exterior silence that allows us to discover an inner place of peace within us.