John answered them all, "I indeed baptize you with water, but he comes who is mightier than I, the latchet of whose sandals I am not worthy to loosen. He will baptize you in the Holy Spirit and fire,

 John was one of the world's supremely effective preachers. Once Chalmers was congratulated on a sermon. "Yes," he said, "but what did it do?" It is clear that John preached for action and produced it. He did not deal in theological subtleties but in life. 