From the Introduction: We do not think that W. Perkins went too far when he said of the Sermon on the Mount, "It may justly be called the key of the whole Bible, for here Christ openeth the sum of the Old and New Testaments." It is the longest discourse of our Lord’s recorded in the Scriptures. He began His public ministry by insisting upon repentance (Matthew 4:17), and here He enlarges upon this vitally important subject in a variety of ways, showing us what repentance really is and what are its fruits. It is an intensely practical sermon throughout: as Matthew Henry expressed it, "There is not much of the credenta of Christianity in it—the things to be believed; but it is wholly taken up with the agenda—the things to be done, for ‘If any man will do His will, he shall know of the doctrine’ (John 7:17)."