We must learn first of all that we ought to pray and not to faint. For the effect of prayer is union with God, and if someone is with God, he is separated from the enemy. Through prayer we guard our chastity, control out temper, and rid ourselves of vanity; it makes us forget injuries, overcomes envy, defeats injustice, and makes amends for sin. Through prayer we obtain physical well-being, a happy home, and a strong, well-ordered society. Prayer will make our nation powerful, will give us victory in war and security in peace; it reconciles enemies and preserves allies. Prayer is the seal of virginity and a pledge of faithfulness in marriage; it shields the wayfarer, protects the sleeper, and gives courage to those who keep vigil. It obtains a good harvest for the farmer and a safe port for the sailor.
Prayer is your advocate in lawsuits. If you are in prison, it will obtain your release; it will refresh you when you are weary and comfort you when you are sorrowful. Prayer is the delight of the joyful as well as solace to the afflicted. It is the wedding crown of the spouses and the festive joy of a birthday no less than the shroud that enwraps us in death.
Prayer is intimacy with God and contemplation of the invisible. It satisfies our yearnings and makes us equal to the angels. Through it good prospers, evil is destroyed, and sinners will be converted. Prayer is the enjoyment of things present and the substance of the things to come. Prayer turned the whale into a home for [Jonah]; it brought Ezechias back to life from the very gates of death; it transformed the flames into a moist wind for the Three Children. Through prayer the Israelites triumphed over the Amelakites, and 185,000 Assyrians were slain in one night by the invisible sword. Past history furnishes thousands of other examples beside these which make it clear that of all the things valued in this life nothing is more precious than prayer.St Gregory of Nyssa, The Lord's Prayer, (New York: Paulist Press, 1954), 24-25