What does Ephesians 6:15 mean?

Roman soldiers typically wore sandals which allowed them to move quickly during battle, and provided protection to their feet. Here Paul imagines the shoes as "the readiness given by the gospel of peace." Shoes made a soldier "ready" to run into battle. The gospel of peace likewise makes a believer ready for spiritual battle. Anyone who has walked around outside with no shoes knows that some areas are virtually off-limits when you're barefoot. Shoes give you the ability to go almost anywhere. Shoes also provide traction. The gospel anchors our faith in certain basic, universal truths. Without that, we'd find our foundation slipping.

One of the modern world's most common problems is stress. Yet the peace given through the gospel is the answer to most of our daily anxiety. We can cast our cares on God because He cares for us (1 Peter 5:7). Further, connecting the concept of "shoes" with the gospel of peace may also suggest the idea of believers taking the gospel into daily battles, sharing it wherever they go (Matthew 28:18–20). Believers are given the gospel of peace in order to be ready for battle and to help others facing spiritual attack.

Those who study martial arts know that setting one's feet is the beginning of all combat. They affect balance, grip, power, and movement. In the same way, the foundation of our day-to-day Christianity is the gospel.