Cyprian on Putting on the Armor of God in 250CE

For the secular contest men are trained and prepared, and reckon it a great glory of their honor if it should happen to them to be crowned in the sight of the people, and in the presence of the emperor. Behold a lofty and great contest, glorious also with the reward of a heavenly crown, inasmuch as God looks upon us as we struggle. … God looks upon us in the warfare, and fighting in the encounter of faith; His angels look on us, and Christ looks on us. How great is the dignity, and how great the happiness of the glory, to engage in the presence of God, and to be crowned, with Christ for a judge!

Let us be armed, beloved brethren, with our whole strength, and let us be prepared for the struggle with an uncorrupted mind, with a sound faith, with a devoted courage. Let the camp of God go forth to the battle-field which is appointed to us. … The Apostle Paul teaches us to be armed and prepared, saying, “We wrestle not against flesh and blood, but against powers, and the princes of this world and of this darkness, against spirits of wickedness in high places.

Therefore put on the whole armor, that you may be able to withstand in the most evil day, that when you have done everything you may stand; having your waist buckled about with truth, and having put on the breastplate of righteousness; and your feet shod with the preparation of the Gospel of peace; taking the shield of faith, with which you shall be able to quench all the fiery darts of the wicked one; and the helmet of salvation, and the sword of the Spirit, which is the word of God.”

Let us take these arms, let us fortify ourselves with these spiritual and heavenly safeguards, that in the most evil day we may be able to withstand, and to resist the threats of the devil: let us put on the breastplate of righteousness, that our breast may be fortified and safe against the darts of the enemy: let our feet be shod with evangelical teaching, and armed, so that when the serpent shall begin to be trampled and crushed by us, he may not be able to bite and trip us up: let us bravely bear the shield of faith, by the protection of which, whatever the enemy darts at us may be extinguished: let us take also for protection of our head the helmet of salvation, that our ears may be guarded from hearing the deadly edicts; that our eyes may be fortified, that they may not see the odious images; … that our mouth may be fortified, that the conquering tongue may confess Christ its Lord: let us also arm the right hand with the sword of the Spirit, that it may bravely reject the deadly sacrifices; that, mindful of the Eucharist, the hand which has received the Lord’s body may embrace the Lord Himself.