The Sermon on the Mount (Matthew 5-7) has attracted a variety of approaches to interpretation:-

1.  The Sermon as an ‘Interim Ethic’.  This was the view of Schweitzer.  Jesus’ sermon sets out a radical ethic to be followed by Jesus’ followers in the light of the imminent end of the age.  However, Jesus was mistaken: the end did not arrive.  This interpretation has serious weaknesses.  The Sermon itself contains no hint of being a short-term ethic.  Jesus himself was no fanatic.

2.  Existential approach.  The Sermon is not a statement of concrete ethical principles, but a challenge to personal decision.  But this is to read modern existential categories back into the biblical text.

3.  The Sermon is meant for this present age, and is to be rigorously obeyed.  One version of this view then finds an antithesis between the teaching of Jesus and that of Paul.  But, in so doing, it ignores the progress of revelation brought about by the cross, resurrection and ascension, and it also neglects the Sermon’s own teaching on the need for grace.  A second version of this view holds to salvation by grace, but that the necessary manifestation this is a life lived in conformity to the precepts of the Sermon (including those about poverty and war).  But this neglects the antithetical manner of Jesus’ teaching and would make Jesus’ teaching on some of these subjects contradict other biblical teaching.

4.  A Lutheran approach is to assert that the demands of the Sermon are impossibly high and are intended to make people aware of their sin and need for forgiveness.  But this can scarcely be supported from the text.  Carson writes: ‘the Sermon on the Mount does indeed drive men and women to a sober recognition of their sin and a realistic understanding of their need for grace. But the Sermon does more than that. It portrays the pattern of conduct under kingdom authority, a pattern that demands conformity now, even if perfection will not be achieved until the kingdom’s consummation.’

5.  Classical liberalism optimistically viewed the Sermon as the ‘real’ gospel in a nutshell.  It provided a blueprint for social progress.  This dream was shattered bu the two world wars.  It was highly selective of the biblical material, neglecting those parts that speak of sin and redemption.  But, as Carson notes: ‘liberalism overlooked the fact that human nature requires forgiveness and help. Fed by an optimistic faith in the inevitability of evolutionary development, liberalism actually displaced the real gospel with a secular philosophy of progress. Quite unaware of the subjectivity of its choices, it selected those parts of biblical revelation conducive to its spirit and theory and rejected the rest. The result provided man with no Savior, no Redeemer, no divine grace, no empowering Spirit; but only a lovely pattern which men subsequently learned they were not able to copy on their own strength.’

6.  A more recent view interprets the Sermon as a collection of catechetical material, some of which may date back to the historical Jesus.  The material would have been preceeded by the preaching of the gospel and by conversion.  It is a call to discipleship for those who are already heirs of God’s kingdom.  The weakness of this approach is that it does not treat Matthew as a serious historical document.

7.  The dispensationalist approach rigidly distinguishes between the law and the gospel and sees the Sermon as an offering of the millennial kingdom to the Jews.  The Sermon is then the law that pertains to that millennial kingdom.  However, because the Jews rejected Jesus as their Messiah, he instigated a second plan, unforseen by OT revelation.  In pursuit of this plan, Jesus delayed the coming of the millennial kingdom and introduced an ‘age of grace’.  This age may be designated ‘the kingdom of God’ (in contrast to ‘the kingdom of Heaven’).  Accordingly, although the Sermon embraces some principles of conduct that are relevant to the Christian it has no direct applicability to us.  Indeed, some of its provisions (e.g. Mt 6:14f) are antithetical to the age of grace.  In the words of the Schofield Reference Bible: ‘The Sermon on the Mount in its primary application gives neither the privilege nor the duty of the Church. These are found in the Epistles.’

The dispensationalist structure is imposed so rigidly that the text is too often not allowed to speak for itself.  Moreover, the proposed antithesis between law and grace is too absolute: salvation has always been by grace, and salvation has always demanded conformity to God’s will as set forth in Mt 5-7.

Moreover, the Sermon presupposes a world such as our own as the sphere in which its demands are to be worked out.  That world includes persecution, anger, litigation, adultery, lying, malice, hypocrisy, insincerity, love of money, worry, judgmentalism, false prophets, and much more.  ‘An era requiring special principles to govern face-slapping and turning the other cheek (Mt 5:39) is hardly one to which the term “millennium” is aptly applied.’ (Carl Henry)

Again: the Sermon gives the clear impression that Jesus intended his words to have lasting validity, rather than that they would have to be postponed.

Finally: The dispensationalist approach is insensitive to the ways in which the NT uses the OT.  The NT writers uniformly see the church as the legitimate successor to believing Israel, the people of God in the OT; they see OT teaching being fulfilled in Christ’s cross-work, resurrection, and the resulting church.

Adapted from Carson, The Sermon on the Mount, 163-170.  See also this, by Sam Storms.