Does religion cause most wars?

from the old testament

• The cause of war is human sin, first actualized in the Garden of Eden (Genesis 3) and testified to by the prophet Jeremiah: "The heart is deceitful above all things, and desperately sick; who can understand it?" (Jeremiah 17:9).
• Sometimes when one nation is wicked, another nation must go to war to stop them from harming innocent people. God wants us to take up the cause of the vulnerable (Psalm 82:3-4).
• God’s wars in the Old Testament were judgements against wickedness. When God told the Israelites he was giving other nations over to them so that they could have the land, He said, “Not because of your righteousness or the uprightness of your heart are you going in to possess their land, but because of the wickedness of these nations the Lord your God is driving them out from before you, and that he may confirm the word that the Lord swore to your fathers, to Abraham, to Isaac, and to Jacob” (Deuteronomy 9:5).

from the new testament

• Jesus confirms that humankind’s wickedness is the cause of all sorts of evil: "For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false witness, slander" (Matthew 15:19).
• The apostle James indicates that sin is the cause of dissension among humankind, which would logically include war: “What causes quarrels and what causes fights among you? Is it not this, that your passions are at war within you? You desire and do not have, so you murder. You covet and cannot obtain, so you fight and quarrel. You do not have, because you do not ask. You ask and do not receive, because you ask wrongly, to spend it on your passions” (James 4:1-3).
• Though governments do not always fulfill God’s command to do justice, God has set them up for that very reason: “For rulers are not a terror to good conduct, but to bad. Would you have no fear of the one who is in authority? Then do what is good, and you will receive his approval, for he is God's servant for your good. But if you do wrong, be afraid, for he does not bear the sword in vain. For he is the servant of God, an avenger who carries out God's wrath on the wrongdoer” (Romans 13:3-4). Many wars are fought to stop evil, not because of religious reasons.

implications for today

Atheists and secular humanists often claim that religion is the number-one cause of violence and war throughout history. For example, atheist philosopher Sam Harris says in his book The End of Faith that faith and religion are "the most prolific source of violence in our history." But we can expose such assertions by simply asking: "How did you come to that conclusion?"

Because in fact the historical evidence shows that secular ideology is a much bigger cause of wars than religion. According to the Encyclopedia of Wars, out of 1,763 known historical conflicts, only 123, or approximately 7%, had religion as their primary cause. When conflicts waged in the name of Islam are excluded, this percentage drops to around 3%. Other studies confirm similar findings, For example, Vox Day (The Irrational Atheist) estimates that only 6% of wars can be classified as religious. William Cavanaugh’s book, The Myth of Religious Violence, also exposes the “wars of religion” claim.

Moreover, the most deadly conflicts in history—such as the two World Wars, the Holocaust, and genocides under communist regimes—were driven by ideological, political, and economic motives rather than religious ones. In fact, many of these regimes were explicitly atheistic, further demonstrating that religion is not a prerequisite for large-scale violence.