"My speech and my preaching was not with enticing words." 1 Cor ii. 1-5.
Paul was a scholar and an orator of the first rank; he is not speaking out of abject humility; but saying that he would veil the power of God if, when he preached the gospel, he impressed people with his "excellency of speech." Belief in Jesus is a miracle produced only by the efficacy of Redemption, not by impressiveness of speech, not by wooing and winning, but by the sheer unaided power of God. The creative power of the Redemption comes through the preaching of the Gospel, but never because of the personality of the preacher. The real fasting of the preacher is not from food, but rather from eloquence, from here are the impressiveness and exquisite diction, from everything that might hinder the gospel of God being presented. The preacher is the representative of God - "as though God did beseech you by us." He is there to present the Gospel of God. If it is only because of my preaching that people desire to be better, they will never get anywhere near Jesus Christ. Anything that flatters me in my preaching of the Gospel will end in making me a traitor to Jesus; I prevent the creative power of his redemption from doing its work.
"I, if I be lifted up ..., will draw all men unto Me."
-- Oswald Chambers, "The Miracle of Belief," My Utmost for His Highest