What use do you make of quotes and illustrations?
I never quote someone just because he is an authority. The Scripture is authoritative and does not need outside support. The only time I quote an authority is on a matter about which Scripture is silent. Usually when I quote a commentator or theologian, it is because he has stated the truth in a clear, definitive, prosaic, or graphic manner. I only quote someone who has said something in a unique way worthy of quoting. I would not quote him just because what he said was true, since I could do this in my own words.
Of course, when I quote someone, I am careful to credit him. To quote someone else as though it were your own words is wrong. Yet I read so many different discussions and pour so many things through my mind as I prepare my sermons that it is next to impossible to document the source of each thought. As long as I phrase the thoughts in my own words and combine them with other thoughts, it is not necessary to footnote them. Extensive footnoting is proper in a book—I am careful in my books to document my sources—but too many references to sources would be distracting in a sermon.
A balance is the ideal. We cannot document every thought in our sermons. On the other hand, we should give credit where due. Pastors sometimes ask me if they can use my material. I have given blanket permission for people to use any thoughts, outlines, illustrations, or insights they find helpful in my sermons or commentaries. If what I say has value to someone, I am honored for him to use it for God's glory. The truth is all His, and I have no personal wish to get credit. As a matter of integrity, however, when we're quoting someone else's words, we ought to acknowledge that fact and cite the source.
When someone preaches another person's sermon without enriching it by going through the discovery process, that sermon will inevitably be flat and lifeless. The great Scottish preacher Alexander Maclaren once went to hear another man preach, a young man with a reputation for being a gifted preacher. Much to Maclaren's surprise, the young man said at the outset of his message, "I've had such a busy week that I had no time to prepare a sermon of my own, so I'm going to preach one of Maclaren's." He did not know Maclaren was in the audience until Maclaren greeted him afterward. He was very embarrassed and became even more so when Maclaren looked him in the eye and said, "Young man, I don't mind if you are going to preach my sermons, but if you are going to preach them like that, please don't say they are mine."
To rely too heavily on the sermons of others robs one of the joy of discovering biblical truth for himself. Such sermons will lack conviction and enthusiasm. Sermons by other preachers should be another study tool, like commentaries or illustration books.
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