In the passage in 2 Corinthians 5:21, the word righteousness means God's approval or being considered right in his eyes. Think of it in this fashion: When God sees you he approves of you because you are a bearer of his righteousness. You are justified in his sight. And as you can tell from seeing the word right, this is a word about taking a stand and doing the right thing. Trying to help poor, oppressed people is a cause full of righteousness. Doing an unpopular thing that is ethical requires righteousness.

Being righteous literally means to be right, especially in a moral way. Religious people often talk about being righteous. In their view, the righteous person not only does the right thing for other people but also follows the laws of their religion. The righteous are people who have entered into covenant with God by faith and seek to live according to his word. The covenant that they have makes them the people of God—God knows them, and because God knows them, they shall never perish.

There is a third kind of righteousness in the Bible, and that is practiced righteousness. Practiced righteousness is our obedience to God once we become a Christian. It is the good works we perform after we are saved. No, good works are not a requirement for salvation, but they should be the result of our salvation. In Matthew 7:17-19, Jesus described practiced righteousness as the fruit of our spiritual life: “So every good tree bears good fruit, but the bad tree bears bad fruit. A good tree cannot produce bad fruit, nor can a bad tree produce good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire.” Simply put, if a tree is alive, it is going to produce fruit. If it is not producing fruit, it is dead and needs to be cut down. James said the same thing in James 2:26: “For just as the body without the spirit is dead, so also faith without works is dead.” If you see a Christian who has no interest in doing good works and obeying God, then that person, no matter what he claims, is spiritually dead. If we are spiritually alive, we are going to practice righteousness.