"Stand therefore, having fastened on the belt of truth, and having put on the breastplate of righteousness, and, as shoes for your feet, having put on the readiness given by the gospel of peace."
In addition to the belt of truth and breastplate of righteousness, Paul now adds the next element of spiritual armor: shoes/boots that give us the ability to stand firm. A good pair of boots allows the soldier to be ready to march, climb, fight, or do whatever else is necessary. Christ demands the same readiness of His people. The verse speaks of a strength and steadfastness which the gospel gives to those who believe, like the firmness which strong boots give to those who wear them.
Our "boots for battle" ... our ability to stand firm ... is found in the gospel of peace. Remember what Jesus said in the gospel of John? "Peace I leave with you; my peace I give to you; not as the world gives do I give to you. Let not your heart be troubled, neither let it be afraid" (John 14:27). It is from this foundation of peace that we must fight the enemy. If our heart is troubled and fearful, we will not be effective in the day-to-day battle against the devil. The peace that Jesus provides is what gives us the strength to stand our ground and hold our point in the battle.
Scripture speaks of two kinds of peace: Positional peace that has to do with our standing before God, and practical peace that has to do with how we apply the reality of that peace to the circumstances and situations we face in life.
Our positional peace is expressed clearly in Romans 5.1: "Therefore, having been justified by faith, we have peace with God." We who trust Christ are redeemed and declared righteous by faith. Our sins are forgiven, and we have peace with God. That was God's wonderful purpose in salvation.
The focal point of the battle, however, isn't with positional peace, but with how we apply that peace in the heat of the battle. The gospel of peace deeply affects how we deal with the circumstances of life. Rather than feeling victimized by events, the gospel of peace transforms the way we see and respond to the situations that we face. It allows us to look beyond any circumstance that confronts us to see the greater purpose of God in our life. When applied properly, the gospel of peace gives us strength of heart and mind.
The transformational message is that the peace that Jesus gives does not refer to the absence of conflict. It is not about "peaceful circumstances." Rather, it is about a Spirit-empowered inner peace -- a condition of heart & mind -- that allows us to see and respond effectively to whatever event or situation we may be facing.
This is the peace that Paul speaks about in Philippians 4:7: "And the peace of God, which surpasses all comprehension, shall guard your hearts and your minds in Christ Jesus." The peace of God is not based on circumstances, so it doesn't always make sense to the unsaved mind. Paul says it is a peace that surpasses comprehension. It doesn't seem reasonable that such peace could exist in the midst of the problems and troubles Christians go through. But this is divine, supernatural peace; it cannot be figured out on a human level.
And that is why Paul says in Ephesians that the gospel of peace is the essential foundation for spiritual warfare. If we are standing strong from a position of peace, we do not overreact when the enemy attacks. We stay calm, focused, alert, and aware. No matter what is happening, we stand firm and hold our point.
It is the biblical "Get Your Mind Right." The quality of your inner response (condition of heart and mind) determines the quality of your outer response (action and behavior). If we see a situation through the lens of fear, anger, frustration, and complaining -- then we will react to the situation directed by the emotions of fear, anger, frustration, and complaining. But if our mind/heart is in a condition of inner peace -- calm, confident, focused -- then we will see the same situation through an entirely different lens, and our response will be much more effective.
It is through the gospel of peace that the guilt of the past is forgiven, the challenges of the present are overcome, and our destiny in the future is secured eternally. It is through the gospel of peace that we live by vision, not by circumstance. The gospel of peace is the necessary foundation for victory in spiritual warfare.
"Rejoice in the Lord always; again I will say, rejoice. Let your reasonableness be known to everyone. The Lord is at hand; do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus." (Philippians 4.4-7)
Trust God, do the work, and embrace the peace of God that passes all understanding.