Ephesians 6:15 (NIV)
15 and with your feet fitted with the readiness that comes from the gospel of peace.
I love when trying to understand scripture to look both at the cultural reference and the deeper spiritual meaning that the writer was trying to convey. Around the time that Paul wrote Ephesians 6, the Roman soldier wore a shoe called a caligae. It was a heavy soled military boot. The design allowed for its adjustment, which would reduce chafing, and had hobnails or cleats in the base to allow for traction and to ease the soldier in pushing forward or holding his ground.
The word “peace” comes from the Greek word eirene (i-ray-nay) which means one, peace, quietness, rest and peace of mind.
Another version says “and your feet shod with the preparation of the gospel of peace ” . Preparation signifies a foundation or base that you are building on.
So as Christians, when we are putting on the feet of peace, it is the constant and firm standing of the Peace of mind in Christ that allows us to have traction, to push forward or to hold our ground in our beliefs, without being moved away from them, that we may continue in them.
Without shoes, we would get our feet dirty or injured. We would not be able to handle anything but smooth easy ground. If the terrain got difficult, it would be too painful to continue, advance, or even stand your ground. The preparation of the gospel of peace allows you to not only stand your ground with the knowledge that God is with you, but it will allow you to take ground that is deemed difficult or hostile.