God is the friend of silence. See how nature -- trees, flowers, grass -- grow in silence; see the stars, the moon, the sun, how they move in silence... The more we receive in silent prayer, the more we can give in our active life. We need silence to be able to touch souls. The essential thing is not what we say, but what God says to us and through us. All our words will be useless unless they come from within.
At the extremity of prayer words vanish, or rather the "silence-become-word" surpasses all that can be uttered. Prayer becomes the silence of Love, and this silence reveals the "I" in its deepest aspects; and, should words suddenly arise in prayer, we must regard them as fruits of love that send us back to silence.