“Yet when a preacher exhorts a congregation on a topic of his choosing, using biblical texts only to back up his point, he will never preach more than what the preacher already knows. Expositional preaching requires more than that. It requires careful attention to the context of a passage, because it aims to make the point of the biblical text the point of the sermon. When a preacher exhorts a congregation by preaching a passage of Scripture in context-where the point of the passage is the point of his sermon- both he and the congregation will end up hearing things from God that the preacher did not intend to say when he first sat down to study and prepare for the sermon.”
~ Mark Dever