Prayer, considered in its nature or quality, is a familiar conversation and union with God; considered in its efficacy, it is the preservation of the world, the reconciliation with God, the mother of tears, the companion on journeys, the propitiation for sins; a bridge over the high waters of temptation; a bulwark against all assaults of afflictions; the suppression and extinction of wars; the office of angels; the nourishment of all souls; the anticipation of future joy; a perpetual occupation; the source of all virtues; the channel of all graces.
Prayer is the lever of the spiritual life; the medicine of the soul; the light of the understanding; the expeller of despair; the ground pillar of Christian hope; the remedy for melancholy and sadness; the riches of monks; the treasure of hermits; the cessation of anger; a mirror to show the progress in the spiritual life; the thermometer of the soul; a declaration of the dispositions of the heart; a moral certainty of heavenly glory.
Prayer is a pious, gentle tyranny toward God, forcing Him to give up to us everything, even Himself.
Key Book by St. John Climachus: Ladder of Divine Ascent - Superb English translation of the original Greek, a valuable addition to the home library of any who are interested in Orthodox spirituality, the history of the Church, or their own spiritual growth. This translation provides the full import and impact of the original Greek with superb footnotes and commentary.