Says one prominent speaker with a smile, "When Chuck Swindoll starts preaching better sermons, so will I." For preachers, using sermon content from others can provoke humor and guilt.
For one thing, we don't always know when to credit other sources. Preaching is like blocking defensive linemen in football: the line between blocking and holding can be as fuzzy as that between research and reliance.
At times the need to credit sources is perfectly clear. Tell someone else's story as though it happened to you? Use an entire sermon without giving credit? Penalty, 10 yards and loss of down, major chewing out from the coach. Most everyone says that's a foul.
At other times, citing a source is a judgment call. If you purchase a sermon or receive permission from the source to use it (Rick Warren says, use my stuff), should you still give credit? If you illustrate from a Time article but get the illustration idea from Joe Stowell, do you credit Stowell? What if you use only another ...