Is a Christian entitled to self-defense? If that is the case, how does that work with the teaching of Jesus that we are to turn the other cheek and go the extra mile?

Should a true follower of Jesus be a complete pacifist? Or can a Christian actually be in favor of war? More specifically, can a Christian, in good conscience, serve in the military or as a law enforcement officer?

These questions have been asked for hundreds of years, and they are valid questions. In the Sermon on the Mount (Matthew 5–7), Jesus deals with this issue and far more.

Jesus delivered the Sermon on the Mount to His disciples. Its standards are not those by which a society is governed as much as they are principles by which a true follower of Jesus is to live. The real theme of the Sermon on the Mount is simply this: the heart of the matter is the matter of the heart.

That is why Jesus saved His most scathing words not for tax collectors or for prostitutes, but for Pharisees. He told them, “Even so you also outwardly appear righteous to men, but inside you are full of hypocrisy and lawlessness” (Matthew 23:28).

Jesus was looking at their hearts. And God is still looking at human hearts today.

Have you ever actually wanted to kill someone? Has someone ever made you so angry that you almost could have? Let me put it another way: Have you ever driven on a freeway during rush hour?

Let’s be honest. We have all felt that kind of anger. This is why we are warned about going “in the way of Cain” in Jude 1:11.

Cain was a murderer. His murderous motive started with envy when he saw that God accepted his brother Abel’s sacrifice over his. That envy ultimately led to murder. And that is why we have to nip these things in the bud.

Jesus said, “But I say to you that whoever is angry with his brother without a cause shall be in danger of the judgment” (Matthew 5:22). The word Jesus used for “angry” in this verse means a settled anger, malice that is nursed inwardly.

 Jesus was speaking of people who become bitter and then develop a grudge and nurse it. They are not letting go. Every day, they are fueling the fire.

This is wrong. And this actually can lead to the kind of sin Jesus was referring to.

There are times when anger is proper. There is such a thing as righteous indignation. Certainly Jesus demonstrated that when He drove the moneychangers out of the temple, not once but twice.

Of course, there is also wicked anger. This is the kind of anger where we let something settle in and turn into hatred. According to 1 John 3:15, “Whoever hates his brother is a murderer, and you know that no murderer has eternal life abiding in him.”

Anger is murder in the heart, just as lust is adultery in the heart. Jesus said, “You have heard that it was said to those of old, ‘You shall not murder, and whoever murders will be in danger of the judgment’ ” (Matthew 5:21). In the original language, the word used in this verse for “murder” is very specific.

Sometimes people will quote this verse and say, “It is a sin to kill. That is why there should be no wars and no one should ever use a gun or try to defend their lives.” But the Bible does not say that. Rather, it says, “You shall not murder.”

Let’s understand the difference. All murder is killing, but not all killing is necessarily murder.

There are times when killing is acceptable, though not desirable. The Bible makes allowance for war. Throughout the Old Testament, there were many occasions when God told the Israelites to go to war. So there is a place for peace and a place for war. There is a place for the use of force and a place for turning the other cheek.

Jesus was not refuting capital punishment or the proper use of force, but He was essentially saying, “You pride yourselves on the fact that you have never actually murdered someone. But have you ever wanted, in your heart, to kill someone?”

If we only focus on the outward, we won’t get to the real issue: Righteousness is a matter of the heart.