The Sermon on the Mount was a kind of inaugural address on the theme: The Ideals of the Kingdom of Heaven. It was a real connected discourse at a definite time and place. It had special application to the twelve just chosen, serving as a kind of ordination sermon. But it was also applicable to the great number of believers present and the multitude of others who had not yet definitely accepted His teaching. Many of the splendid things said on this occasion were repeated at different times later in His ministry. We have only a brief outline recorded by Luke and a somewhat fuller one by Matthew; and by no means all of the things said by Jesus in this sermon are recorded in these outlines. Many of His teachings pronounced on other occasions did not constitute a part of this discourse at all. But He did lay down here, at this critical juncture of His ministry, a platform of important principles for the enlightenment and guidance of His kingdom forces. This sermon is not a mere ethical code but its sublime moral principles far surpass all human moral standards. Christ’s idea of Righteousness as here set forth, became the kingdom’s ideal of Righteousness which has never yet been approximately realized by humanity. In His universal eternal principles in this sermon, Jesus laid the basis for the kingdom work for all time. In one discourse, He superseded all previous standards and set up the new and final religious goal for the human race. He here uttered the final word about character and privilege, conduct and duty, religious ideals, the divine and human relations of men, and the supreme objective and goal in life and how to attain it.

(J. W. Shepard, The Christ of the Gospels: An Exegetical Study, Grand Rapids, Michigan: Wm. B. Eerdmans Publishing Company, 1968 [1939], 176; Excerpt from Chapter XIII, The Organization of the Kingdom)