The preaching of the word of God is a key way that God has ordained to shape men and women into the image of his Son. Hence, preaching is much more than a lecture or talk. It is spiritual war. As Paul Tripp points out in this post, discipleship is not easy for that very reason. It is a war for the human heart.
Preachers are often tempted by the thought that the success of a sermon is dependent upon their eloquence. In this article, Matthew Westerholm makes the case that bad sermons can free preachers from this thought. God can use the simplest truth from the less than eloquent preacher for his glory.
Greek, Hebrew, commentaries, historical contexts, word studies, etc. are all important in the preparation process for the preacher, and while preachers should never minimize their preparation for the sacred task of rightly dividing the word of God there is one thing more important than all the intellectual preparation. H.B. Charles, Jr. argues that the most vital question for the preacher is, “Have you been with Jesus?”