Jesus came to destroy the works of the devil, and a primary expression of the devil's work is sin. Satan uses our sin to open up the door to our being attacked. Throughout the Scriptures, we see that the people of Israel, who were first called God’s holy nation, came under attack whenever they sinned against Him.
Sin opens the door to death (Romans 6:16, James 1:15, 1 Corinthians 15:56). The wages of sin is death (Romans 6:23). People try to fight death, but we should be fighting sin, because it causes death. When the Army is plagued with sin, we cannot fight effectively and conquer externa territory.
The Army of God is a holy, righteous people, a people who have set themselves to oppose all the works of the devil – demonic oppression, spiritual blindness, fear, lies, and so on. Through His Army, Jesus is destroying these strongholds of the enemy.
Come join the Army. There’s a war on our hands, and the battle is fierce.