Ephesians 6:13-20 Therefore take up the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand. Stand therefore, having girded your waist with truth, having put on the breastplate of righteousness, and having shod your feet with the preparation of the gospel of peace; above all, taking the shield of faith with which you will be able to quench all the fiery darts of the wicked one. And take the helmet of salvation, and the sword of the Spirit, which is the word of God; praying always with all prayer and supplication in the Spirit, being watchful to this end with all perseverance and supplication for all the saints— and for me, that utterance may be given to me, that I may open my mouth boldly to make known the mystery of the gospel, for which I am an ambassador in chains; that in it I may speak boldly, as I ought to speak.
God knew that as believers we would be in a battle. This is not a physical battle. This is a spiritual one. God has given us tools for spiritual warfare. Our enemy is not only the devil, it’s also our persecutors. How apostle Paul writes here is compares the armor we need in battle with that of the Roman soldier. We need to put on the full armor of God. The armor is obedience to God. These pieces the girdle, breastplate, shield, and helmet were worn in battle with that of the Roman soldier. He says “stand therefore”. Apostle Paul calls Christians to take a strong position on the spiritual battlefield. The breastplate was a tough piece guarding the Roman soldier in the physical battle. Righteousness and holiness are key features to God. He wants us to use his righteousness to guard us in battle against Satan and his attacks. This means full obedience to Jesus Christ also protects us in battle. The Roman soldier wore special boots in combat. Believers have peace with God and he is on our side. There is also the shield of faith. Our full trust in God protects us from Satan’s temptations and fiery darts. The helmet protected the soldier’s head. The helmet of salvation protects those that are already saved. Satan wants to deceive us into making us think we are not saved but we are.