John Calvin Commentary Ephesians 6:15

"and having shod your feet with the preparation of the gospel of peace;" — Ephesians 6:15 (ASV)

And your feet shod. The allusion, if I am not mistaken, is to the military greaves; for they were always considered 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 unharmed 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 I consider the effect of the gospel to be likewise expressed by this term.

We are enjoined to lay aside every hindrance and to be prepared both for journey and for war. By nature we dislike exertion and lack agility. A rough road and many other obstacles slow our progress, and we are discouraged by the smallest annoyance.

On these accounts, Paul holds out the gospel as the most suitable means for undertaking and performing the expedition. Erasmus proposes a circumlocution, (ut sitis parati,) that you may be prepared; but this does not appear to convey the true meaning.