[Jesus'] object in this Sermon … is to bring Christian people to realize first of all their nature, their character as a people, and then to show them how they are to manifest that nature and character in their daily life. Our Lord, the Son of God, has come from heaven to earth in order to found and establish a new kingdom, the kingdom of heaven … Therefore it is essential that He should make it quite plain and clear that this kingdom He has come to establish is entirely different from anything that the world has ever known, that it is to be the kingdom of God, the kingdom of light, the kingdom of heaven. His people must realize that it is something unique and separate; so He gives them a description of it … We have looked at His general portrait of the Christian in the Beatitudes. We have listened to Him telling these people that, because they are that kind of person, the world will react to them in a particular way; it will probably dislike them and persecute them … [Yet] they are to remain in society as salt and as light. They are to keep society from putrefaction and from falling to pieces, and they are to be … that light, apart from which the world remains in a state of gross darkness.
… He then comes to the practical application and outworking of it all … giving detailed instructions as to how we are to do our almsgiving, and how to pray and how to fast. Finally He deals with our whole attitude towards life in this world … ‘There’, He says … ‘is the character of this kingdom which I am forming. That is the type of life I am going to give you, and I want you to live and manifest it’ … Having done that, He pauses, and looks at His congregation and says, ‘Well, now; there is My purpose. What are you going to do about it? There is no point in listening to this Sermon, there is no purpose in your having followed Me through all this delineation of the Christian life, if you are only going to listen. What are you going to do about it?’