We’ve seen the importance of putting on the breastplate of righteousness as protection against Satan’s attempts to pervert your thinking and emotions. But Scripture speaks of three kinds of righteousness: self-righteousness, imputed righteousness, and practical righteousness. Which did Paul have in mind in Ephesians 6:14?
Paul wasn’t speaking of self-righteousness because that is what the breastplate of righteousness is designed to protect us from.
Similarly, Paul wasn’t speaking of imputed righteousness–the righteousness of Christ granted to every believer at the moment of salvation.
Only practical righteousness remains–that which flows from obedience to God’s Word. Although in God’s eyes we are righteous in Christ, we must also pursue righteous behavior. In other words, our practice should match our position. That’s what Paul meant when he said, “Work out your salvation with fear and trembling” (Phil. 2:13). John added that “the one who says he abides in [Christ] ought himself to walk in the same manner as He walked” (1 John 2:6).