God commands the believer to put on the breastplate of righteousness (Ephesians 6:14). The breastplate is a vital piece of equipment, given that the organs which the breastplate protects are vital, especially the heart. The heart is a vital organ.
The heart is presented in the Bible as the seat of the affections. The heart is where we treasure those things that are precious to us (Matthew 6:21). The heart of fallen man is wicked and estranged from God (Jeremiah 17:9). It desires those things which are evil, but in Christ, the believer is given a new heart with new affections (Ezekiel 36:26). God Himself takes the old heart with its old desires and replaces it with a new heart that treasures the Lord Jesus Christ. This is the heart that must be protected by the breastplate of righteousness.
I heard a pastor preaching on this text once say that the breastplate of righteousness is made of two layers, those are, imputed righteousness and imparted righteousness.
First, the breastplate of righteousness is put on by way of imputed righteousness. Imputed righteousness is the righteousness of Christ, i.e., His having kept the Law of God perfectly, applied to the believer’s account by faith (see 2 Corinthians 5:21 & Romans 3:21-26). The believer, having no righteousness of his own, receives the righteousness of Christ by resting on His finished work and receiving the benefits of salvation by faith. Now, when God looks upon the believer, He sees the work of Christ on his behalf.
The imputed righteousness of Christ as a breastplate is essential to defending against the attacks of Satan because Satan will attack the assurance of the believer by way of accusation. Satan will whisper in your ear, “You couldn’t possibly belong to Christ. You didn’t read your Bible this morning. You spoke harshly to your sibling or spouse yesterday. You can hardly call yourself a Christian.” When Satan sends these fiery darts at the heart of the believer, they bounce off the breastplate with a resounding ring: “I am worse than you even accuse, but I stand righteous not because of my works, but Christ’s!”
Second, the breastplate of righteousness is put on by way of imparted righteousness. While imputed righteousness is the righteousness of Christ received by faith, imparted righteousness is the believer, enabled by God, obeying God’s commands, or practicing righteousness (see 1 John 3:10). Just one way that believers can walk in this imparted righteousness is by walking in the ordinary means of grace, those are, the Word of God, the Sacraments, and Prayer.
Focusing on the Word of God, the believer can defend against the attacks of the evil
I said at the beginning of this post that the heart is the seat of the affections. It’s where we treasure those things that are precious to us. So, what does defending the heart with the breastplate of righteousness by way of imputed righteousness and imparted righteousness have to do with the affections?
To have your affections rightly ordered toward God is the very purpose for which you were made. This is why the answer to the first question of the Westminster Shorter Catechism says,
“The chief end of man is to glorify God and to enjoy him forever.”
The purpose of your life is to enjoy God, to have your heart enraptured with Him for His glory, and Satan is after that purpose. It must be protected.
So then, imputed righteousness and imparted righteousness are not simply cold points of doctrine. They are means by which we treasure Christ in the heart. Our hearts ought to leap when we think of our sin laid on Christ and His righteousness laid to our account by faith. What a glorious and gracious exchange! Walking in Spirit-empowered righteousness ought to be a means by which our affections are stirred for our Savior.
First Peter 2:7a reads:
“Therefore, to you who believe, He is precious…”
You know that you are taking up the breastplate of righteousness if this is true to your heart. You are protecting your heart against the attacks of Satan if you know the Lord Jesus as precious treasure.
Take up the armor of God. Protect your affections against the attacks of Satan. When the devil accuses, send him to Christ who has given you, His righteousness. Run the accuser out with glad obedience to God’s commands. Protect your heart with the breastplate of righteousness.