Summary: We utilize what God has issued us for the conflict. We need protection. Which breastplate are we trusting? Our own, or Christ's righteousness? Don't go to war without the Breastplate of Righteousness.
In today’s military, a critical element of force protection is body armor. The Army issues Kevlar flak vests to soldiers to protect their upper body. DuPont, the manufacturer, claims they’re lightweight, but I’d disagree. It doesn’t take long to feel weighed down. Nonetheless, you wouldn’t want to go to war without one. Kevlar flak vests offer protection from ballistic threats and thermal protection from blasts and fire. They are a modern-day breastplate.
In Bible times, a soldier’s breastplate was usually either a coat of chain-mail or a molded metal chest plate that covered one’s front and back torso, from the neck to the upper thighs, safeguarding vital organs from injury. Paul tells us to stand--and we can--with proper protection: with the “breastplate of righteousness”, an image taken from Isaiah 59:17.
“Righteousness” is doing what is right in God’s eyes; it is purity, holiness, and integrity. It is being of one mind with God. It is ceasing to walk in darkness because we have the light of Christ. Paul wants us to take this spiritual resource and put it to use in our day-to-day battles. Soldiers of God are issued righteousness, which is put to our account. We have none of our own. When we turn to Christ, our sins are no longer held against us; we are given the righteousness of Christ. His purity is credited to us; it becomes part of us. And righteousness is imparted as the Holy Spirit sets us apart and shapes us into the kind of soldiers we need to be.
“Righteousness” means we sustain a disciplined, responsible life. Paul tells the Corinthians, “I keep control of my body and bring it into subjection” (I Cor. 9:27). A soldier is a “lean, mean fighting machine” who has gone through intensive training and drills, maintaining high standards of fitness. In the same way, soldiers of God follow after spiritual-mindedness. Proverbs 11:4 states, “Wealth is worthless in the day of wrath, but righteousness delivers from death.” And Jesus declared in Matthew 5:6, “Blessed are those who hunger and thirst for righteousness, for they shall be filled.”
The word “Righteousness” today is almost always used with a negative connotation. People who are “righteous” are considered rigid and puritanical. “Righteous” in Scripture means to be “up to standard”, presentable (Tim Keller). Soldiers stand at attention in formation while their First Sergeant inspects their uniforms and makes corrections. If any aspect of their uniform isn’t squared away, be sure there will be push-ups! Whether you’ve served in the military or not, no one wants to be unpresentable; no one wants their flaws to show. We want to be pleasing in the eyes of others--parents, spouse, friends, employers. Have you ever shown up at an event improperly dressed? It’s mortifying! If you go to battle without protection, it’s fatal.