Deuteronomy 20:1-4
He shall say: “Hear, Israel: Today you are going into battle against your enemies. Do not be fainthearted or afraid; do not panic or be terrified by them. 4 For the LORD your God is the one who goes with you to fight for you against your enemies to give you victory.”
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Some have argued that non-Christians may fight in wars but believers may not, but this distinction is not found in Scripture. Scripture teaches that it is not sin for a government to engage in a just war, and there is therefore nothing that forbids Christian from being involved in just wars.
Jesus spoke about wars in the context of his prophecies regarding the Last Things and the Second Coming, indicating that “wars and rumors of wars” would occur as part of the signs preceding his return. He didn’t explicitly condemn or condone war, but he emphasized the importance of peace and peacemakers.
The Bible’s stance on war is complex and not a simple yes or no answer. While it emphasizes peace and love, it also acknowledges the need for government to use “the sword” for protection and justice. Some interpretations, like just war theory, suggest that war can be justified under specific circumstances, such as self-defense or defending against unjust aggression, but not for conquest or aggression.
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example: Ukraine vs Russia War [from a discussion with others]
The Ukrainians are fighting a JUST WAR because they are fighting for their freedom, their children, their country, their culture.
The Russians are fighting an UNJUST WAR because they are fighting for covetous reasons — resources, land, World power, etc. — and are the aggressors.
another example: [from a discussion with others]
America taking the land from the American Indians in past history – would have been an unjust war. [covetousness of land, freedom, and resources]
The American Indians fighting for their land and resources in past history – would have been a just war. [protecting their home country, resources, etc.]