God reveals Himself as the divine Warrior who fights on behalf of or against the people who profess to bear His name, depending on their faithfulness to His covenant. While this truth was known under the old covenant (see, for example, Ex. 15:3; Dan. 10:10–14), now under the new covenant we have a clearer perspective on spiritual warfare, especially insofar as we are called to fight on the Lord’s side against the Enemy and his minions.
Paul explains how we are to equip ourselves for this spiritual warfare. In Ephesians 6: 10–12, he reminds us that our struggles with sin and with those people who hate the living God are not battles against flesh and blood but against the Evil One. Before we knew Christ, we were in Adam and enslaved to the powers of sin and death. Having been reconciled to God through Jesus, we no longer have the Devil as our captain but now serve in the army of the Lord (Rom. 5:12–21). Still, the influence of sin does not disappear at once, for the world, the flesh, and the Devil strive to make us forget whose side we are on as servants of the cross (7:7–25; 1 Peter 5:8–9).
The only effective way to keep us from going against the way of Jesus and acting as traitors to His cause is to continually put on the uniform that identifies us as His soldiers (Eph. 6:13–17). Paul uses the analogy of a soldier’s armor to describe the armor of faith. While it is possible to draw some inferences as to the reason why each particular piece of armor is linked to its specific spiritual characteristic, it is more important to see that the roots of Paul’s thinking go back to the Old Testament. In Isaiah 59:15b–17, the prophet speaks of God wearing the same kind of armor as we are to wear in battle against Satan. Putting on spiritual armor simply means that we continually clothe ourselves in the Lord, relying on His gifts and graces to resist temptation and to enable us to risk even our own well-being for the sake of the kingdom.
Continual prayer in the Spirit both for ourselves and for the needs of fellow believers is the means by which we wear this armor (Eph. 6:18–20). Praying in the Spirit is not a mystical experience but rather an alertness to pray, along with a quickness to pray, because, knowing the Holy Spirit intercedes with and for us as we pray, we recognize the power in acknowledging our dependence on God (Rom. 8:26–27).
John Calvin comments on this passage, reminding us that we should not let the “injurious treatment” of others provoke us to revenge, for those who bother us are merely darts from Satan’s hand. “While we are employed in destroying those darts, we lay ourselves open to be wounded on all sides.” Instead, “we must go straight to the enemy, who attacks and wounds us from his concealment — who slays before he appears.”
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