What Commands Govern Warfare in Deuteronomy 20?

Deuteronomy 20 does not allow military strength or human fear to determine how war is waged. Instead, it places warfare under God’s commands. This becomes clear in the regulations that extend from verse 1, where Israel faces its enemies, to verse 20, which governs the treatment of trees during a siege. The passage sets limits from the moment Israel goes out to battle through the actions taken after victory, preventing the Israelites from waging war however they please.

They Were Not to Be Ruled by Fear at the Sight of a Larger Army

The first things the Israelites would see on the battlefield were horses, chariots, and an army larger than their own. God did not deny the reality of what stood before them, but he commanded them not to be afraid. The reason was that the Lord who had brought Israel out of Egypt would be with them.

When the people drew near to the place of battle, the priest was to repeat this message before them. He proclaimed in a series of commands that they must not lose heart, be afraid, panic, or tremble. He then declared that God would go with his people, fight against their enemies, and give them victory. Instead of focusing on the visible difference in military strength, the passage repeatedly directs Israel’s attention to what God had already done and to his continuing presence with them.

Yet the command not to fear did not mean that everyone had to be forced onto the battlefield. Anyone who had built a new house but had not yet dedicated it, planted a vineyard but had not yet enjoyed its fruit, or become engaged but had not yet married could return home. Anyone who was afraid and fainthearted was also required to leave, because his fear could cause others to lose heart as well.

The priest proclaimed that God was with the people, while the officers considered each person’s circumstances and the effect that person might have on the community. Only after this process were commanders appointed to lead the army. Israel did not prepare for war simply by gathering as many soldiers as possible.

They Had to Offer Peace Before Attacking a City

When Israel approached a city to attack it, they first had to offer terms of peace. If the city accepted the offer and opened its gates, its people would become subject to forced labor and serve Israel. Only if the city rejected peace and chose to fight were the Israelites commanded to lay siege to it.

The passage does not treat every city in the same way. Verse 15 explains that this rule applied to cities far from Israel that did not belong to the nations of Canaan. By contrast, in the cities of the land God was giving Israel as an inheritance, the Hittites, Amorites, Canaanites, Perizzites, Hivites, and Jebusites were to be completely destroyed.

Verse 18 directly explains why. These nations might teach Israel to imitate the detestable practices associated with their gods, leading the Israelites to sin against the Lord. The passage therefore distinguishes between cities according to their distance, identity, and the danger that their practices would lead Israel into sin. It does not collapse different groups into a single rule.

They Were Not to Cut Down Fruit Trees, Even During a Long Siege

Even during a prolonged siege, Israel was not to cut down fruit trees, because their fruit would provide food. The passage asks whether the trees of the field are people to be besieged. In doing so, it clearly distinguishes between the city being fought and the trees that produce food.

Even when materials were needed for siegeworks, the Israelites could not cut down trees indiscriminately. They could use only trees known not to bear fruit. The need to continue the siege until the city fell did not justify destroying fruit trees.

The laws of warfare in Deuteronomy 20 do not permit a pattern of gathering troops in fear, launching an immediate attack, and destroying whatever seems useful. Israel had to hear the proclamation that God was with them, determine who should return home, offer peace first to distant cities, and preserve fruit trees even during a siege. God’s commands governed the beginning of the war, its conduct, and the extent of its destruction.

If you are facing something frightening today, read Deuteronomy 20:1–4 and write one sentence describing the threat you can see and another describing what God has done. This simple practice follows the order of the passage: instead of looking only at the size of the enemy, remember that the God who brought Israel out of Egypt is with his people.