I have heard of a ship that was fired at by the cannon in a fort, but no impression was made upon until the general in command gave the order for the balls to be made red-hot and then the vessel was sent to the bottom in three minutes. That is what you must do with your sermons: make them red hot. Never mind if men do say you are too enthusiastic or even too fanatical. Give them red-hot shot.
C.H. Spurgeon (ed Ray Comfort)
From the book "Spurgeon Gold: Pure, Refined"