Black preachers sometimes use the sound of words to make a rhythm. Sometimes this might be a pause for breath. Sometimes the very taking of the breath will make a noise that is a part of the rhythm. Sometimes even the organist joins in with the rhythm.
Henry Mitchell noted that he didn’t always find significant use of rhythm in black sermons, but he still put it in the section on Black Preaching Style. He noted that he has not found a significant use of rhythm in many sermons except for the pause for breath and the use of musical accompaniment to the sermon that often happens today. While that may be true, still the most effective preachers make use of cadence and rhythm. Mitchell correctly notes that the use of rhythm must be genuine and not for show otherwise it might not be received warmly.
Note a master of cadence or rhythm in his use of words, Dr. Martin Luther King. This clip includes parts of various speeches. The video is not the greatest, but I like the rhythmic and poetic use of languge. Note how the clip begins with the way that King says, “Caught up in an inescapable network of mutuality.”