20:1–4 Instructions for warfare begin with an exhortation concerning the role of the military: success is always dependent on God, who fights for his people. Israel does not conduct wars on God’s behalf; rather, God cares and provides for his people when they come under the attack of other nations God has judged. This is the proper definition of “holy war,” as it is sometimes called. The concept is that God provides victory, not that a nation fights for God. It is important to have a well-prepared military, but military success is always dependent on God as the warrior who fights for his people. The model given is that of God’s bringing Israel out of Egypt (v. 1) when Israel did not have an organized military force. God took up the military attack against Pharaoh, finally sinking his armies in the Reed Sea (Ex. 15:1–18). If this is the example of divine warfare, an army should not be necessary at all. But just as the gift of the land did not come about without combat, as Moses reminded Israel in his first sermon, life in the land will also involve war. Most often the enemy will be overwhelming, as was the case with entrance into the Promised Land. But Israel must never fear, because military success is never dependent on the superiority of military forces. And warfare should never be engaged apart from a divine mandate for protection of the covenant people. If warfare is under God’s command, no opposing army should be a cause of terror.

The priests are part of the military operations, as they represent God to the army. Their task is to provide the assurance that God is with them in battle. This is stated first as the central requirement for engagement in warfare. In actual practice, the priest would speak to the army once it had been recruited and was about to engage in battle, as explained in verse 2. Other armies would depend on the power of chariots and horses (v. 1), but Israel would call on the name of the Lord (Ps. 20:7–9). Dependence on military weapons would result in failure; only the Lord could protect his king and the nation. In one outstanding example, Jehoshaphat is overwhelmed by a coalition of kings against him (2 Chron. 20:1–22). He seeks the Lord and assembles his army. His prayer is answered with a prophetic declaration through a Levite (2 Chron. 20:14–17). The Levite explains the route of the attack but exhorts the army not to engage in battle and instead to wait for the salvation of the Lord. In response, Jehoshaphat assembles a Levitical choir at the head of his army to engage the superior forces. Before the opposing army arrives at the scene of battle, its whole coalition collapses into fighting each other. Israel arrives to gather up the spoils. This would not be the procedure of every battle, but it exemplifies the practice Moses explains here. Once the army is assembled, the priests address them with the declaration that, unless the Lord fights for them, their cause is lost. But, conversely, if God is on their side, they cannot lose.

20:5–9 The regulations for mobilizing a voluntary army are motivated by humanitarian concerns. The purpose is to ensure minimal disruption of civilian life. Civilian officials rather than military generals are responsible for the recruitment of the army. Deferments allow for the provision of establishing a home, farm, or family. These are fundamental to community function and the basic entitlement of every person. The opportunity to participate in these basic rights must not be jeopardized. In the case of establishing a family, a marriage has not been consummated, but the bridal price has been paid. In ancient practice this payment was for the benefit of the wife and was the equivalent of her inheritance. Once payment was made, the marriage was initiated, known as “inchoate marriage.”52 This was not an engagement but the beginning of a marriage; any violations to the relationship were treated as violations of a marriage (Deut. 22:23–24). A final reason for deferment was for the benefit of the army; any individual not prepared to engage in warfare should not join, as doing so would demoralize the other troops.

Once membership of the army had been determined by civilian officials, the military officers would take charge. The army generals would be appointed, indicating that the army would be marshaled for specific threats. These are not regulations for a standing force. It is not specified who appoints the army leaders, but it would be officials of higher authority. The procedure may follow the description of the appointment of judges (1:15), in which heads of tribes are appointed based on their wisdom and reputation, and then those heads appoint leaders referred to as chiefs of thousands, hundreds, fifties, and tens. Those chiefs are civilians, while these are to be temporary military leaders.

20:10–14 The general rule in warfare is to seek terms of peace without engaging in battle. If a city accepts terms of surrender, its citizens are not harmed but become part of a state labor force. Solomon uses such a conscripted labor force from the native Canaanite peoples who live as subordinates after the conquest (1 Kings 9:20–21). These laborers are distinguished from the temporary conscriptions Solomon lays on the Israelites to construct buildings (1 Kings 5:13–14). Israelites will never be subject to continuous servitude but will temporarily serve the state, as in the military service described here or in temporary service for building projects. If a city does not accept terms of peace, it will be dealt with more harshly. Its soldiers, who have the potential to lead in a future rebellion, are to be dispatched. The women and children become Israelite servants, though in some cases they might be taken as wives. All the property of the city is taken by the Israelites.

20:15–18 The inhabitants of Canaan fall under the judgment of the kherem, which means that they are removed entirely from the common. The people are put to death because they stand under final divine judgment. Their time of accountability has come; their continuing presence would be a danger to the covenant Israel has with God. Their practices in relation to their gods are an abomination to Israel (18:9–13). This is not an ethnic matter. Israelite cities that adopt abominable Canaanite practices are treated the same way (13:12–16). This regulation is given as a theological reality. Canaanites must be purged so that the covenant of Israel is not compromised with their practices. It is only in select cities such as Jericho that extermination of people and property is carried out in actual practice.

20:19–20 It is common practice in warfare to destroy the infrastructure of invaded territory in order to reduce the resources for resistance. Ancient warfare often involved a long duration of time. Cities were fortified and generally well-supplied in preparation for war. Siege works (Hb. matsor) generally included a wall or fortification built around the city by an attacking army to blockade it from receiving food, military supplies, or soldiers and to protect the attacking army from resistance within the city. This practice was used in Nebuchadnezzar’s attack against Jerusalem, which led to its eventual fall. He built a siege wall around the city, technically called dayeq (a loan word from the Akkadian dajjiqu), and attacked the city for three years (from the ninth to twelfth years of King Zedekiah). By the end of the third year, the city was breached because of famine (2 Kings 25:1–3). A besieging army might use a long siege to threaten a city by destroying its fruit trees and food supply. These regulations prevent such tactics, though they do allow for cutting down non-fruit-bearing trees for building the siege wall. The rationale is the well-being of the tree. Its role in military action cannot be equated with the soldiers’. The statement that trees are not human is both creational and humanitarian. Humans depend on creation; it is to be respected, as it belongs to God, who permits its use by humans.