No matter what the length of the portion explained may be, if it is handled in such a way that its real and essential meaning as it existed in the mind of the particular Biblical writer and in the light of the over-all context of Scripture is made plain and applied to the present-day needs of the hearers, it may properly be said to be expository preaching. It is emphatically not preaching about the Bible, but preaching the Bible. ‘What saith the Lord’ is the alpha and the omega of expository preaching. It begins in the Bible and ends in the Bible and all that intervenes springs from the Bible.*
*The quote is included in Lawson’s, Famine in the Land: A Passionate Call for Expository Preaching (Chicago: Moody Publishers, 2003), 97. Lawson provides the endnote: Merrill F. Unger, “Expository Preaching,” Bibliotecha Sacra 111 (October-December 1954): 333-334.