Rick, here are several memorable quotes on the power of prayer that I came upon while doing research for my Sunday school lessons:
"Prayer turns ordinary mortals into men of power. It brings power. It brings fire. It brings rain. It brings life. It brings God." - Samuel Chadwick, Wesleyan Methodist Minister
"Prayer is the way you defeat the devil, reach the lost, restore a backslider, strengthen the saints, send missionaries out, cure the sick, accomplish the impossible, and know the will of God." - Dr. David Jeremiah
"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