Peter Mead is a Preaching Blog Machine. (I was going to say a Preaching Blog Stud, but thought better of it). I am SO far behind in reading his posts, Jesus will probably come back before I get through them all. He cranks out so many and they are consistently good.
Peter had a very helpful post a couple of weeks back on quoting others. He gave four guidelines. I will give the principles and perhaps one sentence, but you really need to check out the post. Find it here.
1. Make sure you are genuinely comfortable with the quote and its author. This can be particularly significant in a church setting where you would not want to quote certain people unawares.
2. Strive to use quotes from well-known folks. Obscure characters from history, or unknown academics, tend to struggle for effective reception in church circles.
3. Keep quotes punchy. A long quote is a long quote, but hardly ever an effective quote.
4. Verbally frame your quote. When you have that one that works so well, that will support or clarify or drive home your point, then don’t waste it. It is better to verbally frame it, to set it up so they are listening for it. Perhaps pulling a card from your inner pocket or Bible, pausing and then reading it, will work much better than simply saying it from memory. The goal is not to read, but to make sure listeners hear. The movement, the visual element and the pause all help to highlight and press bold on your verbal quote.