The Sermon on the Mount is often confusing to biblical interpreters. In this section, Jesus emphasizes the importance of the OT law and moral obedience. However, the apostle Paul writes that believers are not under law (Rom. 6:14; 7:6). Some interpreters claim that this is hopelessly contradictory, while others use this section of Scripture to support the notion that Christians should be under law. However, we feel that this is misguided for a number of reasons:
REASON #1: Jesus was targeting the legalistic, religious Pharisees in this sermon.
The Pharisees were trying to lower the demands of the Law, so Jesus was opening his public ministry by raising the standard back to where it belongs: perfection. Jesus says, “You are to be perfect, as your heavenly Father is perfect” (Mt. 5:48). While the Pharisees believed that they were morally righteous enough to enter into God’s presence, Jesus claims that the true standard for heaven is perfection. Earlier he says, “Unless your righteousness surpasses that of the scribes and Pharisees, you will not enter the kingdom of heaven” (Mt. 5:20). His implication is clear: Even the legalism of the Pharisees is not good enough for God. Consider Jesus’ correction of the Pharisees’ false beliefs regarding legalistic righteousness.
Jesus versus the Pharisees
Pharisees’ False Belief
“I’ve never murdered anyone, so I’ve perfectly kept the Law.”
|“I say to you that everyone who is angry with his brother shall be guilty before the court” (Mt. 5:22).|
|“As long as I don’t commit adultery, then I will be saved.”||
“I say to you that everyone who looks at a woman with lust for her has already committed adultery with her in his heart” (Mt. 5:28).
“I have been divorced according to the arbitrary rules of Pharisaical law.”
“I say to you that everyone who divorces his wife, except for the reason of unchastity, makes her commit adultery” (Mt. 5:32).
REASON #2: Jesus was preaching the LAW in the Sermon on the Mount—not GRACE.
When Jesus preached to legalistic people, he spoke on the impossibility of gaining righteousness through the law. For instance, in Luke 10:25-28, Jesus spoke with a religious expert:
(Lk. 10:25-28) A lawyer stood up and put Him to the test, saying, “Teacher, what shall I do to inherit eternal life?” 26 And He said to him, “What is written in the Law? How does it read to you?” 27 And he answered, “You shall love the Lord your God with all your heart, and with all your soul, and with all your strength, and with all your mind; and your neighbor as yourself.” 28 And He said to him, “You have answered correctly; do this and you will live.”
Why would Jesus offer this path to salvation, when Paul states that no one could ever achieve it (Rom. 3:23)? The answer is clear: The crushing weight of the law shows us our need for forgiveness. Paul writes, “The Law has become our tutor to lead us to Christ, so that we may be justified by faith” (Gal. 3:24). In the Sermon on the Mount, Jesus is really offering two different paths of salvation: Plan A or Plan B.
Plan A: You can approach God by earning salvation through good works. If you can meet God’s standard, you will earn eternal life.
Plan B: You can approach God by trusting Christ for his good works and death on the Cross. No one meets God’s standard, so you desperately need Christ.
We might capture Jesus’ logic in a disjunctive syllogism like this:
Either Plan A or Plan B.
Not Plan A.
Therefore, Plan B.
No one can follow the law perfectly. Jesus knew this, so did Paul (Gal. 3:10), and so did James (Jas. 2:10). In the Sermon on the Mount, Jesus said that if you were even angry at your brother, you would go to hell (Mt. 5:22). He said that if you had lust in your heart, you would go to hell (Mt. 5:28-29).
A critic of C.S. Lewis disparaged him for holding to preferring the “Pauline ethic,” rather than that of Jesus. Indeed, the man charged Lewis of not caring for the Sermon on the Mount. To this, Lewis replied,
As to ‘caring for’ the Sermon on the Mount, if ‘caring for’ here means ‘liking’ or enjoying, I suppose no one ‘cares for’ it. Who can like being knocked flat on his face by a sledgehammer? I can hardly imagine a more deadly spiritual condition than that of a man who can read that passage with tranquil pleasure.
So true! If anyone—Christian or not—can read through the Sermon on the Mount without realizing his utter need for forgiveness, something is terribly wrong! By showing the impossibility of living under law, Jesus was pushing his listeners to take grace seriously. Paul (a former Pharisee) learned this lesson. He writes, “I no longer count on my own righteousness through obeying the law; rather, I become righteous through faith in Christ. For God’s way of making us right with himself depends on faith” (Phil. 3:9 NLT).
REASON #3: The Sermon on the Mount should be understood through the lens of the new covenant and the work of the Cross.
The Sermon on the Mount does offer ethics for believers today. However, it would be a mistake to ignore the fact that this sermon was given under old covenant theology—not the new covenant. It was given before Jesus paid for our sins on the Cross. Consider Jesus’ teaching on forgiveness for example:
OLD COVENANT: (Mt. 6:15) If you do not forgive others, then your Father will not forgive your transgressions.
NEW COVENANT: (Eph. 4:32) Be kind to one another, tender-hearted, forgiving each other, just as God in Christ also has forgiven you.
NEW COVENANT: (Col. 3:13) Bearing with one another, and forgiving each other, whoever has a complaint against anyone; just as the Lord forgave you, so also should you.
While forgiveness was conditional in the old covenant, it is unconditional in the new. Since Christ fulfilled the law for us (Mt. 5:17; Rom. 10:4), we are no longer obligated to keep the law as believers. Paul writes, “You are not under law but under grace” (Rom. 6:14). Elsewhere he writes, “We have been released from the Law, having died to that by which we were bound, so that we serve in newness of the Spirit and not in oldness of the letter” (Rom. 7:6).
In the Sermon on the Mount, Jesus says, “If you ignore the least commandment and teach others to do the same, you will be called the least in the Kingdom of Heaven” (Mt. 5:19 NLT). What does this statement mean? Legalistic teachers argue that Jesus is referring to hyper-grace teachers here, who ignore the law and teach licentiousness.
However, law-teachers ignore the fact that this sermon was not written for the licentious, but for the legalists. Law-teachers will often diminish Jesus’ commands in this passage as being hyperbolic or exaggerating for effect. For instance, regarding Jesus’ claim to cut off our hand instead of lusting, Donald Hagner writes, “The point of these admonitions is clear without pressing for a literal understanding of the words… This is the language of hyperbole used to make a significant point.” Likewise, Martin Lloyd-Jones writes,
Our attitude towards the law, therefore, is most important. Our Lord has not come to make it easier for us or to make it in any sense less stringent in its demands upon us. His purpose in coming was to enable us to keep the law, not to abrogate it. So He emphasizes here that we must know what the law is, and then must keep it: ‘Whosoever therefore shall break one of these least commandments, and shall teach men so, he shall be called the least in the kingdom of heaven.
Law-teachers lower the commands of the Sermon on the Mount in order to make these laws capable of human fulfillment. This is the irony of Lordship theology: In its desire to uphold the Law, they lower what the Law actually demands. In fact, legalistic teachers (the Pharisees) are the type of people that Jesus was targeting in this sermon. Just as the Pharisees were lowering the bar of the law, modern day legalistic teachers will lower Jesus’ statements to be within the believer’s reach. By contrast, grace-teachers believe that Jesus fulfilled the law completely (Mt. 5:17; Rom. 10:4), and he ignored nothing in the perfect law of God.
 C.S. Lewis, The Essential C.S. Lewis (Simon and Schuster, 1996), p.347.
 Emphasis mine. Hagner, Donald A. Word Biblical Commentary: Matthew 1-13. Texas: Word, 1995. (Mt. 5:27-28)
 Lloyd-Jones, David Martin. Studies in the Sermon on the Mount. Grand Rapids, MI: Wm. B. Eerdmans Publishing Company, 1976. 174.