"You can do more than pray after you have prayed, but you cannot do more than pray until you have prayed. Pray often, for prayer is a shield to the soul, a sacrifice to God, and a scourge to Satan."

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...the power of prayer can never be overrated. They who cannot serve God by preaching need not regret. If a man can but pray he can do anything. He who knows how to overcome with God in prayer has Heaven and earth at his disposal.

— Charles Spurgeon