Thou shall not kill?


I had a question from my sister that I couldn’t answer properly. She asks me why I believed in the commandments, especially the fifth, if God told nations in the old testament to kill? Isn’t that a contradiction? I don’t believe so, but I couldn’t explain it fully.


Catechism of the Catholic Church

2263 The legitimate defense of persons and societies is not an exception to the prohibition against the murder of the innocent that constitutes intentional killing. "The act of self-defense can have a double effect: the preservation of one’s own life; and the killing of the aggressor. . . . The one is intended, the other is not."65

65 St. Thomas Aquinas, STh II-II,64,7, corp. art.


Hebrew has two different words for “kill.” One of them, harag (הָרַג) covers a broad range of meanings. It can designate any kind of killing, though it is normally used only of killing a person, not of slaughtering an animal for sacrifice. The other word, ratsach (רָצַח) means, more specifically, “murder.” Killing an enemy in war is always harag, never ratsach. But ratsach is the word that appears in the Ten Commandments.

The Bible Hub website lists all the verses where each of the two words is used:


Understanding Scripture fully can be a difficult task-varied as the bible can be-and that’s why we need the Church to decipher both Scripture and her lived experience, her Tradition, in order to know and correctly teach on God’s nature and will for man. And the Church teaches as has been posted above so far, among very many other things about faith and morals that may or may not seem to contradict personal readings.

The distortion of the Old Testament depiction of God is probably the most common objection to God out there.
Your sister is objecting to a distorted view of God rooted in fundamentalism. Catholics do not read the scriptures in a rigidly literalist way. Her objection to distorted conceptions of God come out of a moral sense that is well tuned. So good for her. Not so good to have a limited sense of Scripture.

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Please, find me a single saint before the last few decades who took this stance, and some biblical commentary to back it up.

You are distorting God. Bartholemew actually answered the question.


Here is the traditional and long standing teaching from the Roman Catechism:

Execution Of Criminals

Another kind of lawful slaying belongs to the civil authorities, to whom is entrusted power of life and death, by the legal and judicious exercise of which they punish the guilty and protect the innocent. The just use of this power, far from involving the crime of murder, is an act of paramount obedience to this Commandment which prohibits murder. The end of the Commandment- is the preservation and security of human life. Now the punishments inflicted by the civil authority, which is the legitimate avenger of crime, naturally tend to this end, since they give security to life by repressing outrage and violence. Hence these words of David: In the morning I put to death all the wicked of the land, that I might cut off all the workers of iniquity from the city of the Lord.

Killing In A Just War

In like manner, the soldier is guiltless who, actuated not by motives of ambition or cruelty, but by a pure desire of serving the interests of his country, takes away the life of an enemy in a just war.

Furthermore, there are on record instances of carnage executed by the special command of God. The sons of Levi, who put to death so many thousands in one day, were guilty of no sin; when the slaughter had ceased, they were addressed by Moses in these words: You have consecrated your hands this day to the Lord.


Thank you, @Godservant!


Right, but the objection is not to just war theory. Most everyone gets that.
The (rightly founded) objection is to the God who

BartholomewB’s language meanings are very informative and convey the relative meanings used. That will not really answer the objection for most people.

Have you read the Bible? Like actually read it beyond the lectionary? Because He’s definitely done that, and it is consistent with both testaments.


Right I will read the bible some more thanks.
If you’ve read the bible with the mind of the Church you probably know that we (Catholics) don’t do fundamentalism. Obviously these passages document God ordering genocide, and anyone who can read can see that battles took place, and killing, and the command of God to slaughter children.

Do you know what fundamentalism is in regards to scripture? Can you explain it in your own words?

Do you have a comment on the specifics of Pope Benedict’s Verbum Domini, secs 42 and 44? Do you trust P Benedict?

and God bless you we are accomplishing nothing other than edifying those who are reading, and that’s all that matters.

I have already told you three times I replied to it. You are free to read that reply.

Interesting. Here is a Catholic source affirming it was a literal command of God:

“ Killing In A Just War

In like manner, the soldier is guiltless who, actuated not by motives of ambition or cruelty, but by a pure desire of serving the interests of his country, takes away the life of an enemy in a just war.

Furthermore, there are on record instances of carnage executed by the special command of God. The sons of Levi, who put to death so many thousands in one day, were guilty of no sin; when the slaughter had ceased, they were addressed by Moses in these words: You have consecrated your hands this day to the Lord.

You keep accusing me of not using the Catholic interpretation yet I’ve taken the interpretation of the Church and Her saints.

Now, let me ask you this, is this phrase wrong?

“Go up against the land of the rulers, and punish the inhabitants thereof, waste, and destroy all behind them, saith the Lord: and do according to all that I have commanded thee.”

Did God just order them to destroy and lay waste to the inhabitants and rulers of the land? Or is the prophet saying God said something He did not? (Note, this is not Moses).

Now, again I ask you to find biblical commentary prior the last few decades to say it was not factual. If you want to convince me it isn’t a factual account I need actual evidence it isn’t.


From the Catechism of St. Thomas Aquinas (which was from the 1930’s):

The Execution of Criminals.–Some have held that the killing of man is prohibited altogether. They believe that judges in the civil courts are murderers, who condemn men to death according to the laws. Against this St. Augustine says that God by this Commandment does not take away from Himself the right to kill. Thus, we read: “I will kill and I will make to live.”[5] It is, therefore, lawful for a judge to kill according to a mandate from God, since in this God operates, and every law is a command of God: “By Me kings reign, and lawgivers decree just things.”[6] And again: “For if thou dost that which is evil, fear; for he beareth not the sword in vain. Because he is God’s minister.”[7] To Moses also it was said: “Wizards thou shalt not suffer to live.”[8] And thus that which is lawful to God is lawful for His ministers when they act by His mandate. It is evident that God who is the Author of laws, has every right to inflict death on account of sin. For “the wages of sin is death.”[9] Neither does His minister sin in inflicting that punishment. The sense, therefore, of “Thou shalt not kill” is that one shall not kill by one’s own authority.[10]


And finally, here is something from St. Thomas Aquinas:
“Reply OBJ 1: God is Lord of death and life, for by His decree both the sinful and the righteous die. Hence he who at God’s command kills an innocent man does not sin, as neither does God Whose behest he executes: indeed his obedience to God’s commands is a proof that he fears Him.”

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But they did kill innocent people sometimes when they conquered a group. They also started fights and didn’t just fight out of self defense

So there are always the two cases and the Jews were know to make errors:

  • following commands of God,
  • disobeying commands of God.

I was going to correct you, goout, and say that not all Catholics read the bible that way. But Godservant has saved me the trouble.

To me, the commandment is related to humans avoiding evil. Taking a person’s life is evil. On the other hand, God can give life and can take it away, so of course He is above this commandment. This is why Abraham intended to follow God’s commandment to kill his own son.

“Now a step further. Does loving your enemy mean not punishing him? No, for loving myself does not mean that I ought not to subject myself to punishment - even to death. If you had committed a murder, the right Christian thing to do would be to give yourself up to the police and be hanged. It is, therefore, in my opinion, perfectly right for a Christian judge to sentence a man to death or a Christian soldier to kill an enemy. I always have thought so, ever since I became a Christian, and long before the war, and I’ still think so now that we are at peace. It is no good quoting ‘Thou shaft not kill.’ There are two Greek words: the ordinary word to kill and the word to murder. And when Christ quotes that commandment He uses the murder one in all three accounts, Matthew, Mark, and Luke. And I am told there is the same distinction in Hebrew. All killing is not murder any more than all sexual intercourse is adultery. When soldiers came to St John the Baptist asking what to do, he never remotely suggested that they ought to leave the army: nor did Christ when He met a Roman sergeant-major- what they called a centurion. The idea of the knight - the Christian in arms for the defence of a good cause is one of the great Christian ideas. War is a dreadful thing, and I can respect an honest pacifist, though I think he is entirely mistaken, What I cannot understand is this sort of semi-pacifism you get nowadays which gives people the idea that though you have to fight, you ought to do it with a long face and as if you were ashamed of it. It is that feeling that robs lots of magnificent young Christians in the Services of something they have a right to, something which is the natural accompaniment of courage - a kind of gaiety and whole-heartedness.”

Mere Christianity, Book 3, Chapter 7. C.S. Lewis

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You are correct, goout; most people will not be satisfied by BartholomewB’s very informative answer. But that’s only because most people don’t bother to learn about the basic elements of their Faith and because the Church apparently has better things to do then insist on correct English meanings in the Bible, even where dogma is concerned.
Most Catholic versions of the English Bible teach people that it’s OK for a man to divorce his wife and marry another if his wife, for example, acted lewdly. Matthew 19:9 NAB. What Our Lord actually said, of course, was that only in the case of an invalid first marriage may people divorce. NAB Revised.
But kill/murder, lewd conduct/invalid first marriage, what’s the difference for most people, right?

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