Opinion has been much divided concerning the design, scope, and application of the Sermon on the Mount. Most commentators have seen in it an exposition of Christian ethics. Some have regarded it as the setting forth of a "golden rule" for all men to live by. Others have dwelt upon its dispensational bearings, insisting that it belongs not to the saints of the present age but to believers within a future millennium. Two inspired statements, however, reveal its true scope. In Matthew 5:1-2, we learn that Christ was here teaching His disciples. From Matthew 7:28-29, it is clear that He was also addressing a great multitude of the people. Thus, it is evident that this address of our Lord contains instruction both for believers and unbelievers alike.
It needs to be remembered that this sermon was Christ’s first utterance to the general public, who had been reared in a defective Judaism. It was possibly His first discourse to the disciples, too. His design was not only to teach Christian ethics, but to expose the errors of Pharisaism and to awaken the consciences of His legalistic hearers. In Matthew 5:20, He said, "Unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven." Then, to the end of the chapter, He expounded the spirituality of the Law so as to arouse His hearers to see their need of His own perfect righteousness. It was their ignorance of the spirituality of the Law that was the real source of Pharisaism, for its leaders claimed to fulfill the Law in the outward letter. It was therefore our Lord’s good purpose to awaken their consciences by enforcing the Law’s true inner import and requirement.
Adapted from The Beatitudes, Introduction, by A.W. Pink.