And your feet shod. The allusion, if I mistake not, is to the military greaves; for they were always reckoned a part of the armor, and were even used for domestic purposes. As soldiers covered their legs and feet to protect them against cold and other injuries, so we must be shod with the gospel, if we would pass unhurt through the world. It is the gospel of peace, and it is so called, as every reader must perceive, from its effects; for it is the message of our reconciliation to God, and nothing else gives peace to the conscience. But what is the meaning of the word preparation? Some explain it as an injunction to be prepared for the gospel; but it is the effect of the gospel which I consider to be likewise expressed by this term. We are enjoined to lay aside every hinderance, and to be prepared both for journey and for war. By nature we dislike exertion, and want agility. A rough road and many other obstacles retard our progress, and we are discouraged by the smallest annoyance. On these accounts, Paul holds out the gospel as the fittest means for undertaking and performing the expedition. Erasmus proposes a circumlocution, (ut sitis parati,) that ye may be prepared; but this does not appear to convey the true meaning.

And your feet shod - There is undoubtedly an allusion here to what was worn by the ancient soldier to guard his feet. The Greek is, literally, "having underbound the feet;" that is, having bound on the shoes, or sandais, or whatever was worn by the ancient soldier. The protection of the feet and ankles consisted of two parts:
(1) The sandals, or shoes, which were probably made so as to cover the foot, and which often were fitted with nails, or armed with spikes, to make the hold firm in the ground: or.
(2) with "greaves" that were fitted to the legs, and designed to defond them from any danger. These "greaves," or boots 1-Samuel 17:6, were made of brass, and were in almost universal use among the Greeks and Romans.
With the preparation - Prepared with the gospel of peace. The sense is, that the Christian soldier is to be prepared with the gospel of peace to meet attacks similar to those against which the ancient soldier designed to guard himself by the sandals or greaves which he wore. The word rendered "preparation" - (ἑτοιμασία hetoimasia) - means properly readiness, fitness for, alacrity; and the idea, according to Robinson (Lexicon), is, that they were to be ever ready to go forth to preach the gospel. Taylor (Fragments to Calmet's Dic., No. 219) supposes that it means, "Your feet shod with the preparation of the gospel; not iron, not steel - but patient investigation, calm inquiry, assiduous, laborious, lasting; or with "firm footing" in the gospel of peace." Locke supposes it to mean," with a readiness to walk in the gospel of peace." Doddridge supposes that the allusion is to "greaves," and the spirit recommended is that peaceful and benevolent temper recommended in the gospel, and which, like the boots worn by soldiers, would bear them safe through many obstructions and trials that might be opposed to them, as a soldier might encounter sharp-pointed thorns that would oppose his progress.
It is difficult to determine the exact meaning; and perhaps all expositors have erred in endeavoring to explain the reference of these parts of armor by some particular thing in the gospel. The apostle figured to himself a soldier, clad in the usual manner. Christians were to resemble him. One part of his dress or preparation consisted in the covering and defense of the foot. It was to preserve the foot from danger, and to secure the facility of his march, and perhaps to make him firm in battle. Christians were to have the principles of the gospel of peace - the peaceful and pure gospel - to facilitate them; to aid them in their marches; to make them firm in the day of conflict with their foes. They were not to be furnished with carnal weapons, but with the peaceful gospel of the Redeemer; and, sustained by this, they were to go on in their march through the world. The principles of the gospel were to do for them what the greaves and iron-spiked sandals did for the soldier - to make them ready for the march, to make them firm in their foot-tread, and to be a part of their defense against their foes.

Your feet shod - The κνημιδες, or greaves, have been already described; they were deemed of essential importance in the ancient armor; if the feet or legs are materially wounded, a man can neither stand to resist his foe, pursue him if vanquished, nor flee from him should he have the worst of the fight.
That the apostle has obedience to the Gospel in general in view, there can be no doubt; but he appears to have more than this, a readiness to publish the Gospel: for, How beautiful upon the mountains are the feet of him that bringeth good tidings, that publisheth Peace; that bringeth good tidings of good, that publisheth salvation; that saith unto Zion, Thy God reigneth! Isaiah 52:7; Romans 10:15.
The Israelites were commanded to eat the passover with their feet shod, to show that they were ready for their journey. And our Lord commands his disciples to be shod with sandals, that they might be ready to go and publish the Gospel, as the Israelites were to go to possess the promised land. Every Christian should consider himself on his journey from a strange land to his own country, and not only stand every moment prepared to proceed, but be every moment in actual progress towards his home.
The preparation of the Gospel - The word ἑτοιμασια which we translate preparation, is variously understood: some think it means an habitual readiness in walking in the way prescribed by the Gospel; others that firmness and solidity which the Gospel gives to them who conscientiously believe its doctrines; others, those virtues and graces which in the first planting of Christianity were indispensably necessary to those who published it.
Should we take the word preparation in its common acceptation, it may imply that, by a conscientious belief of the Gospel, receiving the salvation provided by its author, and walking in the way of obedience which is pointed out by it, the soul is prepared for the kingdom of heaven.
The Gospel is termed the Gospel of peace, because it establishes peace between God and man, and proclaims peace and good will to the universe. Contentions, strife, quarrels, and all wars, being as alien from its nature and design, as they are opposed to the nature of Him who is love and compassion to man.

And your feet shod with the (k) preparation of the gospel of peace;
(k) The preparation of the Gospel may be as it were shoes to you: and it is very fitly called the Gospel of peace, because, seeing we have to go to God through most dangerous ranks of enemies, this may encourage us to go on bravely, in that you know by the doctrine of the Gospel, that we are travelling to God who is at peace with us.

And your feet shod with the preparation of the Gospel of peace. The Gospel is so called, because it makes men to be of peaceable tempers and behaviour, and gives peace to distressed minds: it directs the way to eternal peace, and publishes peace made by the blood of Christ; and has a much better claim to this name, and epithet, than the law has, which is often called "peace" by the Jews (l): the "preparation" of it does not design a promptitude or readiness to preach the Gospel, or to receive it, or profess it, or to give a reason of faith in it, or to endure reproach and persecution for it; nor that readiness which the Gospel is a means of, as for every good work, for the spiritual warfare, for the Christian's journey heavenward, or for heaven itself: but the word signifies a "base", or foundation; and so it is used by the Septuagint interpreters on Zac 5:11; and here it designs a firm and solid knowledge of the Gospel, as it publishes peace by Jesus Christ, which yields a sure foundation for the Christian soldier to set his foot upon, and stand fast on; it being that to him, as the shoe is to the foot, its base or foundation: and for the feet to be "shod with" it, does not mean the outward conversation being agreeably to the Gospel, though such a walk and conversation is very beautiful and safe, and such may walk and war with intrepidity: but it designs the constant and firm standing of believers in the faith of the Gospel, and so striving and contending for it, without being moved from it, that it may continue with them. Shoes or boots, which were sometimes of iron, and sometimes of brass, are reckoned among the armour of soldiers (m).
(l) Zohar in Numb. fol. 73. 3. Tzeror Hammor, fol. 9. 3. (m) Pausan. l. 6. p. 362, 378. Julian. Orat. 2. p. 105. Alex. ab Alexandro, l. 6. c. 22.

Translate, "Having shod your feet" (referring to the sandals, or to the military shoes then used).
the preparation--rather, "the preparedness," or "readiness of," that is, arising from the "Gospel" (Psalm 10:17). Preparedness to do and suffer all that God wills; readiness for march, as a Christian soldier.
gospel of peace--(compare Luke 1:79; Romans 10:15). The "peace" within forms a beautiful contrast to the raging of the outward conflict (Isaiah 26:3; Philippians 4:7).

And your feet shod with the preparation of the gospel - Let this be always ready to direct and confirm you in every step. This part of the armour, for the feet, is needful, considering what a journey we have to go; what a race to run. Our feet must be so shod, that our footsteps slip not. To order our life and conversation aright, we are prepared by the gospel blessing, the peace and love of God ruling in the heart, Colossians 3:14-15. By this only can we tread the rough ways, surmount our difficulties, and hold out to the end.