Paul says in Ephesians 6:15 that the readiness of this gospel of peace is to be put on like shoes as part of our spiritual armor. " . . . and having shod your feet with the readiness of the gospel of peace." … Verses 11–12 say, "Put on the whole armor of God, that you may be able to stand against the wiles of the devil. For we are not contending against flesh and blood, but against the principalities, against the powers, against the world rulers of this present darkness, against the spiritual hosts of wickedness in the heavenly places."

The Context of Having Our Feet Shod

1. All Life Is War
From the cradle to the grave, life is war. Your soul, your mind, your body, your family, your career are fields of conflict. Until Satan is finally thrown into the lake of fire, our peace with God will have to be a vigilant peace. Because Satan will certainly give us no peace if we are at peace with God.

2. The War Is Against Supernatural Evil Powers
The war we are in is not a war with flesh and blood but with supernatural evil powers. What amazes me about Paul's words here is not what he affirms but what he denies. I'm not surprised to hear him say that we wrestle with evil angelic, demonic, supernatural powers. What surprises me is that he says (in v. 12) we do NOT wrestle with flesh and blood.

I want to say to Paul, "You've been stoned and beaten and imprisoned and run out of town and shipwrecked. Your flesh has been torn and your blood has been spilt and that has hindered your ministry again and again. The flesh of others has torn your flesh and the blood of others has boiled against your blood. What do you mean you don't wrestle against flesh and blood? It's people with their hands and their stones and rods and chains that have cost you dearly and tested your faith almost to the limit."

I think Paul would answer. "You're right. Flesh and blood is real and it can be very evil. But what I mean is this. Whenever someone's flesh attacks me, or someone's blood boils against me, or my way is hindered by man, something else is also going on, something deeper, bigger, more terrible, more sinister, more destructive than meets the eye. I don't mean that flesh and blood can't hurt or hinder the cause of Christ. I mean that the prince of the power of the air is more dangerous than any of his subjects and that he must be overcome in every instance of conflict, or the battle is lost."

Consider Ephesians 2:1–2. "And you he made alive when you were dead in the trespasses and sins in which you once walked following the course of this world, following the prince of the power of the air, the spirit that is now at work in the sons of disobedience." Sure, the sons of disobedience (in their flesh and blood reality) can oppose us in our spiritual warfare; but it's more decisive to defeat the spirit that works in them and the prince of the power of the air that they follow, than simply to wrestle as though all you are dealing with is human nature.

So the first thing we see in verses 11–12 is that life is war, and the second thing we see is that the conflict, if it is going to be successful, will be fought with supernatural, demonic forces. If they are not engaged, the victory is superficial.

3. There Is Danger of Falling in This Battle
The third thing we see is that there is danger of falling in this battle. Three times Paul tells us to take pains to stand, that is, not to fall. We've just spent several weeks on this issue of perseverance in the book of Hebrews so we need not dwell on it here.

4. God Has Made Provision for Us to Stand
The fourth thing we see in these verses is that God has made provision for us so that we can stand and not fall. And that provision is armor. God is able to keep us from falling, Jude says, and the way he keeps us from falling is by fitting us for successful spiritual combat. So if your aim is to persevere in the Christian life and not be defeated by the wiles of the devil, then you must put on the armor described in these verses. This is how God means to keep us safe unto the day of salvation.

Having Our Feet Shod with "Readiness"

That's the context in which we read about having our feet shod with the readiness of the gospel of peace (verse 15). Notice that we are not shod with the gospel. The gospel is the word of God and the word of God is our sword according to verse 17. We are not shod with the gospel. What we are shod with is the READINESS of the gospel. Now what does that mean?

Ready to Move with the Gospel
I think it means, "Let your feet be ready to move with the gospel." Feet are for moving from one place to another. If you put on shoes of readiness, then the idea would seem to be readiness to do what feet are for, namely, moving. And if the readiness is readiness of the gospel it probably means ready to move with the gospel—move with gospel power and for gospel purposes.

Let me show you two or three reasons why I think this is the right interpretation.

The Background of Isaiah 52:7
It's almost certain that Paul has in mind here the words of Isaiah 52:7,

How beautiful upon the mountains are the feet of him who brings good tidings, who publishes peace, who brings good tidings of good, who publishes salvation, who says to Zion, "Your God reigns."

Here we have a picture of the feet of people who are running to bring good news, and the good news is good news of peace. Surely this is where Paul got his imagery. And if so, then the "readiness of the gospel of peace" is surely a readiness to move with the gospel, a readiness to tell the good news, and publish peace and say "God reigns!"

The Structure of Colossians 3–4
Here's another reason I think this is what Paul has in mind, and this is really interesting. Notice in Ephesians 6 that the passage on spiritual warfare comes right after the passage on husbands and wives, children and parents, and masters and slaves. Well, if you turn to Colossians 3, near the end you see that the same three pairs are dealt with—wives and husbands (3:18–19), children and parents (3:20–21), and masters and slaves (3:22–4:1). But then instead of a paragraph on spiritual armor Paul calls for vigilant prayer (4:2–4), and look what he says in verses 5–6,

Conduct yourselves wisely toward outsiders, making the most of the time. Let your speech always be gracious seasoned with salt, so that you may know how you ought to answer every one.

Here in a context much like the one in Ephesians is an exhortation to be alert to how you can be the salt of the earth, to answer unbelievers' questions, and to make the most of the time for the sake of Christ. This is what I think Paul means by the readiness of the gospel of peace. Being prepared and being alert and ready to talk about the gospel.

A Parallel in 1 Peter 3:15
One last confirmation: In 1 Peter 3:15 the very word "ready" is used in the same kind of exhortation. "Always be ready to make a defense to any one who calls you to account for the hope that is in you, yet do it with gentleness and reverence."

Experiencing the Power of the Gospel

So, coming back to Ephesians 6:15 I have one last observation. The armor of God is given to us believers to help us stand against the devil. It is introduced as defensive armor. Verse 13: "Take the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand." How to stay standing is the issue.
So what can we conclude from the fact that the shoes of verse 15 are the readiness to move with the gospel of peace? I conclude this. A ready offense is an essential part of a successful defense. And O how true this is!

Giving the gospel away is one of the best ways of experiencing its power in your own life. The best way to taste the power of God for your own soul is to venture something on it. It's the great old truth of the Lord himself when he said, "He who loses his life for my sake and the gospel's will save it." The more ready we are to move with the gospel, the more life and power and joy and security we will know in the gospel.

In giving we will receive. In dying we will live. And in telling the gospel we will hear it again with O so much more depth and power and joy.

How lovely on the mountains
are the feet of him
who brings good news, good news,
proclaiming peace,
announcing news of happiness:
Our God reigns! Our God reigns!

The above content is from Ready to Move with the Gospel of Peace | Desiring God