Holy War Instructions

In the book of Deuteronomy chapter 20 the author has listed some specific rules for conducting war. What are these rules?  Well, first he quotes God saying, "When you go to war and see your powerful enemy remember Egypt". Why is it they must remember Egypt? This is rehearsed in the Seder meal also, that God delivered them with a great victory even though they were nothing. He reminds the children of Israel of Egypt and His victory over the great armies of the Pharaoh.  First article of war is that your enemy even though mightier is going to be defeated by God. The second article is similar to the first. He commands the priest to address the army and point out that fear of the superior forces should not be upon them because God is going to be the one who fights and "saves you". So to prove His point, he commands the third article of war. He tells the officers  to thin the army. The third step in waging war, the officers tell the men to go home!   They seem to look for categories of excuses for the soldiers to go home. They tell them, if you have just bought a house, go home; if you are engaged, go home; if you have planted a vineyard, go home and lastly if you are scared, go home! If you are scared? Who is not scared before a battle? Does God want to win? The key to the thinning of the army may be found in verse four. "For it is the Lord who goes with you into battle to give you the victory." The Lord wanted to make sure that he was the one who would get the glory. For the Lord its all about the glory. It is His. The Lord seems to be looking for His glorification from the battle and the  defeat of His enemies. The song of Moses on the other side of the red sea comes to mind (Exodus 15). "For He has triumphed gloriously" are the words of Moses.  We see this same approach to war in the army of Gideon. God has Gideon thin the army down from thousands to 300! The cry rang out "for the Lord and for Gideon" as the small army won the battle. God's Wars are very important. They had to be carried out correctly. It was God's War God's way. Before going out the priest had to speak to the army, as in 1 Samuel and other places, the priest offered an offering to the Lord in preparation for battle. Often going into battle the worshipers went out in front of the army. And after the war the people offered up the plunder to the Lord. Dr.T. Longman has done a study of the God of War. He looked at the Psalms and determined that of the 150 Psalms, 50 are written concerning war. A good example is Psalms 44 especially verse 3 that declares (one of the articles of War)
        "It was not by their sword that they won the land,

nor did their arm bring them victory;

it was your right hand(God's), your arm,

and the light of your face, for you loved them.

Looking closer at 1 Samuel 13 we can see a great example of how God demands his articles of war to be followed. Here Saul is waiting for Samuel to come and make the pre-battle offering to the Lord. The whole army is waiting.The first seven verses set the stage by telling us the size of the enemy (numbered as the sands of the seas and its force of chariots and horses). So God has the 1st rule setup. Then the verses tell us that the army is "quaking with fear". So aligning these verses with Deuteronomy 20 Saul should have let the fearful go. According to God's articles of war he  should have let them go home. In fact that is what the next verse tells us, the army was scattering. Maybe the soldiers knew the articles too and knew if they were scared they should go home. Saul definitely should have known this and released them to go home and seen it as a sign that God was with him. Instead what did he do? He got fearful himself and tried to do the job for Samuel. He forgot that God is the one who gives the victory. The very next  chapter gives us an example of how it is done correctly. It is the story of Jonathan and his armor bearer. "The lord is not limited by many or by few" was Jonathan's faithful remark. He proceeded to kill 20 Philistines and put fear in the hearts of the Philistines army. Why does God demand the war to be fought with disportionate numbers? Maybe without faith it is impossible to please him as it tells us in Hebrews. And maybe as Dr. Longman has suggested Holy War to God was an act of worship! Later on in chapter 17 of 1 Samuel we see the same scenario repeated. The anointed worshiper David enters the battle as the underdog. In the face of overwhelming odds, he gives the glory to God and declares the "this day the Lord will deliver you into my hand." David, fresh with the anointing of Samuel, knew that the deliverance came from the Lord. Saul hiding in his tent had forgotten how to wage war for the Lord. 
Application?  Spiritual warfare may be the continuation of God's Holy war against evil in "heavenly places". In chapter 6 of Ephesians Paul exhorts us to put on the whole armour of Saul, no, of God. The armour David had on when he faced Goliath. We see Paul espousing the 1st article of war in verse 10, "Finally, my brethren, be strong in the Lord, and in the power of his might". Put on the whole armour of God.  Offer praise before the battle and worship after the battle. This is God's war God's way.