Bryan Chapell gives this wonderful picture of what it is like to put on the armor of God (Ephesians 6):
The way I visualize this truth—that we are enabled by confidence in the armor God provides—follows very precisely the imagery of Paul. I can imagine looking out through the faceplate of the helmet of salvation that God has given me. Coming toward me I see the assaulting forces of the Evil One with all his dominions, powers, and authorities. Simply seeing the approaching cloud of darkness from this mighty enemy, I fear that I cannot stand. The ground shakes, and my knees begin to buckle.
Then, the apostle Paul—like a general on the field of battle—calls out, “Steady now. Do not retreat. Take your stand. Be strong, in the power of his might. Forget the strength you thought you could provide. Remember the might of the armor God has given you. Resurrection power has given you a breastplate of his righteousness, the shield of faith, feet that are shod with readiness that comes from being at peace with the Sovereign of the universe. Beyond all of these defenses, he has given you an ultimate weapon, the sword of the Spirit that is the Word of God. Now, confident of the strength and integrity of the armor that you have been given, stand firm.”
Is there any degree of human effort in resisting sin? Yes, of course there is.17 Already we have discussed the faith, church, and family patterns that are God’s means of nurturing Christian health. In addition, study of God’s Word, commitment to righteousness, and the proclamation of the gospel are means by which we are readied to repel Satan. Richard Foster personally articulates the responsibility that every maturing believer assumes:
"[T]hrough the Holy Spirit’s guidance and strength, I will order my life according to an overall pattern that conforms to the way of Christ. Over time this process will develop deeply ingrained habits in me so that, at the moment of crisis, inner resources to act in a Christlike manner are available."
Chapell, Bryan (2003-02-10). Holiness by Grace (pp. 148-149). Good News Publishers. Kindle Edition.