Matthew 18:6 “If anyone causes one of these little ones—those who believe in me—to stumble, it would be better for them to have a large millstone hung around their neck and to be drowned in the depths of the sea.

Mark 9:42 “If anyone causes one of these little ones—those who believe in me—to stumble, it would be better for them if a large millstone were hung around their neck and they were thrown into the sea.

Exodus 22:2 “If the thief is found breaking in, and he is struck so that he dies, there shall be no guilt for his bloodshed.”

The Bible provides many circumstances under which the taking of a life is legally allowed by Scripture. As the author of the first five books of the Bible, Moses would not have written contradictory ideas. If we allow for killing to be wrong in every case, when a person carried out capital punishment, as commanded by God, they would have to be killed for the taking of a life. Then their life would be demanded, and so on until humanity was left with one. Extending the logic allows us to see how absurd the claim of a contradiction truly is.

The Bible provides many circumstances under which the taking of a life is legally allowed by Scripture. Killing another person in an act of self defense (Exodus 22:2) was permitted with no consequences. There are examples of God calling the people to war against other nations to punish them for their sins. When Joshua led the children of Israel into the Promised Land, God commanded the Israelites to utterly destroy the idolatrous peoples who inhabited the land (Deuteronomy 20:16–17). A list of their sins can be found in Leviticus 18, including incest, murdering children, and so on. When God called Israel to war against those in the Promised Land, then He was permitting the killing in this situation, making men His agents of justice, as in the case with capital punishment.

The killing of Goliath by the young David was, likewise, justified in the eyes of God. In fact, David was angered by the way that Goliath blasphemed God and met him in battle. David did not trust in himself, but in the Lord to deliver Goliath into his hands. This is an example of continuance of the war the Israelites had been engaged in with the inhabitants of the Promised Land, as directed by God.

Even before this, Cain was afraid of the other members of his family seeking to kill him after he had murdered his brother Abel (Genesis 4:13–15).1 In the cases outlined in Scripture, taking the life of another in the name of justice was not murder. The question poses a false dilemma in that killing does not have to be always right or always wrong—God has provided qualifications.