In the Sermon on the Mount, Jesus said: “Think not that I came to destroy the law or the prophets: I came not to destroy, but to fulfil. For verily I say unto you, Till heaven and earth pass away, one jot or one tittle shall in no wise pass away from the law, till all things be accomplished” (Matthew 5:17–18, ASV).
The Old Testament pointed to Jesus as the promised Messiah; Jesus would not destroy that which affirmed his messiahship. The Covenant Law of the Old Testament would later be replaced by the New Covenant of Christ, as predicted in Jeremiah 31:31-34, and affirmed as changed in Hebrews 8:6-13 (see also Romans 7:6-7; Ephesians 2:11-16). But, at the time of this sermon, the Law of Moses is still in effect, and Jesus fulfilled the covenant perfectly.
It’s agreed that the Sermon on the Mount presents ethical content. In the Sermon on the Mount Jesus discusses “Kingdom” living mostly in general principles rather than particular precepts (though some precepts are covered).
• A precept is a moral teaching applied to specific cases.
• A principle prescribes a course of conduct; it is the source of precepts.
The principles of the kingdom are grounded in the nature of God; morality and truth originate in his nature and character. Matthew chapter 5 ends with: “Ye therefore shall be perfect, as your heavenly Father is perfect” (Matthew 5:48).
“Perfect” can also be rendered “complete,” carrying the idea of maturity. Flawless perfection is beyond us, but maturity in godliness, in its biblical concept, is not. Grounded in the character of God, and calling us to live in mature conformity with his character, the ethical requirements in the Sermon on the Mount are lofty and high. Here, not only are the underlying principles of the Law of Moses, but the standard of conduct in the “Kingdom” Jesus and John the immerser were preaching as “at hand” (Matthew 3:1-2 and 4:17).
The Sermon on the Mount has application from the time it was given until the second coming. It’s the will of God regarding covenant living under Christ in a sinful world. The intent is that it be obeyed. The principles outline ethical and moral living of a sort that is more absolute than the Old Covenant, for we find, unlike the Old Covenant, Jesus doesn’t make concession for man’s hardness of heart (the concessions continued until the change of Covenants).
Jesus concludes the Sermon on the Mount saying: “Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father who is in heaven. Many will say to me in that day, Lord, Lord, did we not prophesy by thy name, and by thy name cast out demons, and by thy name do many mighty works? And then will I profess unto them, I never knew you: depart from me, ye that work iniquity. Every one therefore that heareth these words of mine, and doeth them, shall be likened unto a wise man, who built his house upon the rock:and the rain descended, and the floods came, and the winds blew, and beat upon that house; and if fell not: for it was founded upon the rock. And every one that heareth these words of mine, and doeth them not, shall be likened unto a foolish man, who built his house upon the sand: and the rain descended, and the floods came, and the winds blew, and smote upon that house; and it fell: and great was the fall thereof” (Matthew 7:21-27).