Though some of the entries are quite dated, many of the 7700 illustrations are still usable and quite helpful in The Encyclopedia of 7700 Sermon Illustrations: Signs of the Times by Paul Tan. It’s a huge book, but still can be found used for a semi-reasonable price. There is an updated version of 15,000 Illustrations that is even larger and bulkier (Amazon link here). It is considerably more expensive, but could possibly be twice as useful as the older version (I have only used the older version). I believe Logos may sell an electronic version as well.
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