Samuel Brengle was once asked, "If you had but ten minutes to prepare for a meeting (sermon), how would you spend it?" To this Brengle replied, "In prayer."
A ministerial student asked, "What preparation do you make in preaching?"
"My lifetime has been a preparation for preaching. But, more particularly, I prepare my sermons for others by preparing my own heart. In this, prayer and Bible study are the chief factors. When I read books other than the Bible, they are read not that parts of them might be included in my address, but to enrich my own thought and to quicken and inspire my faith. Thus, I spend a great deal of time preparing myself for preaching. Many make the mistake of giving more time to the preparation of their addresses than to the preparation of their own hearts, affections, emotions and faith; the result often is beautiful, brilliant words that have the same effect as holding up glittering icicles before a freezing man. To warm others -- and is not that your purpose in preaching? -- keep the fire buring hot in your own soul."
-- from Samuel Logan Brengle: Portrait of a Prophet by Clarence W. Hall