NOTES for Eph 6:11-12
Paul, of course, does not accidentally describe the Christian path as a path of spiritual warfare. He especially emphasizes that the issue is not war with people, 'against flesh and blood,' but precisely with those spiritual forces which from within this world oppose the Kingdom entering it. The Kingdom enters the world through Christians, and therefore war is inevitable.
The apostle lists what can help a Christian in this war, comparing his spiritual equipment with the weapons of a warrior taking part in earthly battles: helmet, sword, shield, and breastplate or armor. The foundation of everything is faithfulness to truth and righteousness: they are like a warrior's belt and breastplate, without which no battle is possible. Indeed, righteousness is the foundation of the Christian path; refusal of the path of righteousness makes Christian life impossible.
This path itself was known in the pre-Christian era; righteousness as the practice of building conscious relationships with God was known already before the exile, and with the coming of Christ it did not disappear at all. On the contrary, new possibilities were opened to those walking this path, possibilities of which they previously could not even dream. But naturally, if a person refuses the path, he also refuses the new possibilities opening to him. The shield that protects the Christian during spiritual confrontation is faith: faith not as conviction in the truth of certain propositions and principles, but as trust in Christ.
It is precisely this that will save in critical situations when nothing else can help. Paul calls the word of God the sword. And the issue is not only Sacred Scripture, as this verse is usually interpreted, but also, and above all, the living revelation that allows a person to live according to the inner Torah, striving to realize in Christ the ideal of the living Torah. This is how the apostle sees the path of the Christian opposing the dark forces that have seized this world.