“It is the purpose of the passage that must be uppermost. This is true just as well for delivery as for anything else: God’s purpose must control all. All error in preaching, in one way or another, stems from placing our own purposes or personalities above God’s.
The Bible exalts Christ, not men. He should be seen in a sermon, not the preacher who becomes more visible than Christ because of his unbecoming delivery. In every respect, including his use of delivery, the preacher must put Christ first.
This point becomes clear in the interplay between content and delivery at every stage. If God’s purpose in a passage is solemn and grim, your delivery must not make light of it, either intentionally or unintentionally. If God’s purpose is a joyful one, you dare not grind that through a personality grid that is so inflexible and insensitive that the message comes out drab or even solemn. In short, you must allow even your personality to be changed , if and when necessary, by God’s truth. A minister of the Word, when faithful to his calling, in every becomes just that—one in whom the Word has absolute sway, even to the point of great personality change in him. The delivery you should seek, then, is a delivery that is formed, informed, and influenced by God’s truth. The best preacher is one who allows his voice and body to become a well-tuned instrument in the hands of the Holy Spirit. He is willing, therefore, to be stretched, squeezed, and otherwise altered to meet every demand necessary to preaching the whole counsel of God.”
Taken from Preaching with Purpose, p. 155.