‘When you pray,’ it has been wisely said by an Orthodox writer in Finland, ‘you yourself must be silent. . . . You yourself must be silent;let the prayer speak.’ To achieve silence: this is of all things the hardest and the most decisive in the art of prayer. Silence is not merely negative — a pause between words, a temporary cessation of speech — but, properly understood, it is highly positive: an attitude of attentive alertness, of vigilance, and above all of listening. The hesychast, the person who has attained hesychia, inner stillness or silence, is par excellence the one who listens. He listens to the voice of prayer in his own heart, and he understands that this voice is not his own but that of Another speaking within him.