Deuteronomy 20 What do I know about war? It is not something I have dealt with directly or have any real knowledge of.. except that it is a horrible thing in so many ways..
The Lord gave Moses words to instruct and encourage the people of Israel as they were about to enter the land of promise. They were definitely going to battle.
The Lord instructed that the priest would come before the army before they engaged in battle, "And he shall say to them, 'Hear O Israel, you are approaching the battle against your enemies today. Do not be fainthearted. Do not be afraid, or panic, or tremble before them, for the Lord your God is the one who goes with you, to fight for you against your enemies, to save you.' "
Then the Lord gave some unexpected instructions.. He excused from battle those who had just built a house, planted a vineyard, was about to get married, and even those who were afraid. He wanted the willing and able to fight in His army.
He allowed the people to make peace agreements with those nations that were far from the new land.. but they had to destroy all the people that He was removing from His chosen land.
Then one other interesting command.. don't destroy the fruit trees. Use the other trees as needed for seigeworks.. but keep the trees that they could eat from. A word of hope for a future in the land. God had already provided what they would need.
This war was going to be extensive.. but it was the Lord's battle and He would bring victory. The Israelites just needed to trust and obey.
We know that we have an enemy. This war has been waged since the beginning of time, starting in the Garden and continuing until the Day when Christ returns and the enemy is defeated for eternity. We are part of God's army and we are given the same instructions that Israel received.. Don't be afraid, don't panic, don't tremble.. remember that the Lord fights for us.. to save us! We have been given armor for this battle that is "not against flesh and blood.. but against the rulers, against the powers, against the world forces of this darkness, against the spiritual forces of wickedness in the heavenly places."
Let us trust in the Lord, putting on truth, righteousness, the gospel of peace, the shield of faith and the sword of the Spirit. Let us stand firm and not be fainthearted. Our God is on our side and He is fighting for us. Praise You Father, Son and Holy Spirit! Amen.