“Simplicity in expression is of utmost importance. The teacher should speak so that even children and people who cannot read may be able to understand him, as far as the natural mind can comprehend the things of God. Every congregation has people of various educational and social backgrounds. The expounder of the truth of God speaks for God and for eternity. It is unlikely that he will benefit the hearers unless he uses plain speech.
If the speaker strives to speak according to the rules of this world, he may please many, particularly those who have a literary taste. But he is less likely to become an instrument in the hands of God for the conversion of sinners or the building up of the saints. Neither eloquence nor depth of thought makes a truly great preacher. Only a life of prayer and meditation will render him a vessel ready for the Master’s use and fit to be employed in the conversion of sinners and in the edification of the Saints.” ~George Mueller.