A post from Justin Taylor's blog.
A helpful TGC Asks with answers from Tim Keller, Don Carson, and David Murray to the question, “How would you caution teachers intent on preaching Christ in the Old Testament?”
Here is Keller’s answer:
1. Don’t “get to Christ” so soon in the sermon that you don’t unfold the meaning and application of the text to the original hearers. If you “jump to Christ” too soon that often means you inspire people but you don’t give them concrete application for how they are supposed to live.2. Don’t “get to Christ” so late in the sermon that he seems like an add-on, a mere devotional appendix. If you wait too long to get to Christ listeners won’t see how Jesus’ work is crucial if the listeners are going to obey or heed the text.3. Don’t get to Christ artificially. This is a big subject of course, but I believe two of the best ways are (a) by identifying in your text one of the many inner-canonical themes that all climax in Christ (Don Carson’s language), and (b) identifying in your text some “Fallen Condition Focus,” some lack in humanity that only Christ can fill (Bryan Chapell’s language).