Romans 1:9

Romans 1:9. For God is my witness, whom I serve with my spirit in the gospel of his Son, that without ceasing I make mention of you always in my prayers;

This man, Paul, did a great deal by prayer. I remember a minister, who is now with the Lord, who was thanked by his people for his wonderful sermons; but he said to them, "You never thanked me for my prayers, yet they were the best part of my service for you." When men of God are mighty in prayer, we owe much to them.