Ephesians 6:10-20 — The Breastplate of Righteousness

From Truth to Righteousness
Last week, we said that the first piece of the armor of God is truth. Truth is not found merely in abstract propositions, theological assertions, and doctrinal statements. Truth is found in the person of the Lord Jesus who said, "I am ... the truth" (John 14:6). We must stand in truth in order stand against the schemes and deception of the devil. Truth then allows us to have the second piece of the armor, righteousness.

What is Righteousness?
Righteousness is the quality of being morally right according to the standard. However, who sets this standard? Since God is the Creator and this is His world, He alone set this standard. More than that, the standard of righteousness is an expression of God's character, namely, who God is. Therefore, righteousness is moral perfection according to God's standard of holiness. So, achieving righteousness is a humanly impossible task.

God's Righteousness
Because we cannot satisfy the demand of God's holiness and His standard of righteousness, He "demonstrates His righteousness" by sending His Son to atone for our sin (Romans 3:25-26). This why the Lord Jesus told the Jews:

John 8:31-32
“If you abide in My word, you are My disciples indeed. And you shall know the truth, and the truth shall make you free.”

Ironically, although they had been slaves in Egypt, and although they were under the oppression of the Assyrians, the Babylonians, the Medo-Persians, the Greeks, and then the Romans during Jesus' earthly ministry, they said, we "have never been in bondage to anyone. How can You say, ‘You will be made free’?”" (John 8:33). The Lord Jesus had to make it clear to them that He is referring to their bondage to sin. They can only be free from sin by abiding in Him. There was their Messiah, the personified righteousness, and they did not recognize Him. They should have remembered Jeremiah 23:5-6.

Jeremiah 23:5-6
5 “Behold, the days are coming,” says the Lord,
“That I will raise to David a Branch of righteousness;
A King shall reign and prosper,
And execute judgment and righteousness in the earth.
6 In His days Judah will be saved,
And Israel will dwell safely;
Now this is His name by which He will be called:
THE LORD OUR RIGHTEOUSNESS.

The Lord Jesus is not only the truth, but He is also our righteousness.

Imputed vs Imparted Righteousness
Because the Lord Jesus paid the penalty of sin on the cross, those who believe in Him and put their trust in the completed work of Christ on the cross are now declared righteous. This righteousness, the righteousness of Jesus Christ the Son of God, is imputed to them. Imputed means it was credited to us without us earning it. In Romans 4, the apostle Paul outlines the righteousness of Abraham who "believed in the Lord, and it was accounted it to him for righteousness" (Romans 4:22, also cf. Genesis 15:6). To stand against the wiles of the devil, we must understand that our justification, our righteous standing before God, is in no way depends on us, except that God is gracious so we merely come to Him by faith.
Nevertheless, in our spiritual warfare, if we do not want to give the devil a foothold (Ephesians 4:27), we must "pursue ... holiness" (Hebrews 12:14). We do that by pursuing sanctification. While justification (imparted righteousness) declares us righteous, sanctification progressively makes us righteous. While justification takes away the penalty of sin from us, sanctification takes away the power of sin in our lives. This is imparted righteousness.

To stand against the wiles of the devil we need both to have right standing before God (imputed righteousness) and to pursue holiness (imparted righteousness). This is what it means to put on righteousness as a breastplate (Ephesians 6:14b).