10 Finally, be strong in the Lord and in the strength of his might. 11 Put on the whole armour of God, that you may be able to stand against the schemes of the devil.12 For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places. 13 Therefore take up the whole armour of God, that you may be able to withstand in the evil day, and having done all, to stand firm. 14 Stand therefore, having fastened on the belt of truth, and having put on the breastplate of righteousness, 15 and, as shoes for your feet, having put on the readiness given by the gospel of peace. 16 In all circumstances take up the shield of faith, with which you can extinguish all the flaming darts of the evil one;17 and take the helmet of salvation, and the sword of the Spirit, which is the word of God, 18 praying at all times in the Spirit, with all prayer and supplication. To that end, keep alert with all perseverance, making supplication for all the saints."
Ephesians 6:10-18
As to the armour itself (14ff) Paul speaks twice of the 'whole armour of God', and the need to take it and put it on. The word in the Greek is 'panopleia', a word which denotes 'complete coverage'. There is complete protection, Paul means, in Christ, against all the wiles of the devil. And now, the 'whole armour' is broken up into its several component parts, as white light is broken up into the colours of the spectrum when passed through a crystal. We may be meant to think of the various parts of the armour as being the answer to the different forms of attack that the evil one can bring upon us - for example, as Hinderer, Destroyer, Accuser, Angel of light, Tempter, and so on. This can be a helpful way of looking at the various parts of the armour. We mentioned earlier that the phrase 'the evil day' refers not so much to the final crisis of history as to each recurrent crisis in spiritual experience, when battle is joined with the enemy. This must surely mean that the armour must be put on before the attack comes and in the quiet hours. It is too late to be reaching for your armour when the enemy is upon you!
We should note that the first five pieces of the armour are all defensive, and that the last two - the sword of the Spirit and the weapon of all prayer - are for attack. The defensive parts of the armour are designed to guard us against the attacks of the enemy, as has been said. The first of these is the girdle of truth. The imagery here is certainly that of the soldier, and the girdle was the belt which gathered in the soldiers tunic, and from which his sword hung, giving him freedom of movement. We need not press the imagery overmuch, or too far, but the picture is surely that of a soldier prepared for battle and ready for action.