Three times in his epistles Paul speaks of the Christian's armor. He speaks of it to the Romans, to the Corinthians, and to the Ephesians. It is the Ephesians that he admonishes to "put on the whole armor of God."
It is interesting to consider the significance of armor in the eyes of Paul and his insistence that it be put on in its entirety. In speaking of armor to the Romans, Paul describes it as light. "Let us therefore cast off the works of darkness, and let us put on the armor of light," he writes (Rom. 13: 12). And it is as light that the Christian Scientist learns to regard his armor.
Christian Science teaches that spiritual enlightenment is the only armor which is able to resist the darkness of fear, of confusion, of divided allegiance. He who has put on this armor is unafraid. He may be unaware of what the demands upon his skill, his endurance, his fortitude, will be, but equipped with the discernment whereby he is alert to what is real and what is unreal, he is confident of victory. And this, because armor of light is also, in Paul's words to the Corinthians, "armor of righteousness." In this armor of right knowing the Christian warrior is enabled, as he points out, to cast down all that is not of God, thus "bringing into captivity every thought to the obedience of Christ" (II Cor. 10:5).