Playing the Instrument
Called the Human Voice
'Preaching is an oral art form played on the instrument of the human voice. Preachers should learn how to play their instruments as effectively as any singer or instrumentalist. The mastery of oral communicaiton involves the intentional manipulation of the vocal devices of pitch, pace, pause and volume. These four elements ought to be in evidence throughout the sermon. Vocal variation is the essence of effective speech in all settings, and preachers should work hard to master these four devices. With the possible exception of Louis Armstrong's singing style, oral communication that employs one single note is boring and uninspiring. Of course, while Armstrong was noted for his one-note singing technique, when he played his trumpet he made full use of the variations in pitch, pace, pause and volume.'
--From a new book by Rev. Marvin A. McMickle (who has been preaching since the age of 16), The Star Book of Preaching. You can browse all his books here.