Righteousness, today, is God given justification whereby a believer can stand before God without any sense of guilt, condemnation, or shortcomings. It is being "right" before God. Righteousness is not something that can be earned by good works. Righteousness is given to a person by God when that person accepts Jesus Christ's work in his or her place. When you confess with your mouth the Lord Jesus and believe in your heart that God raised him from the dead, God makes you righteous. (Romans 10:9-10) You are saved, born again, given sonship, justified and made righteous. None of this is based upon your works. You receive from God because you have accepted Jesus Christ as your Lord and believed that God raised him from the dead. Righteousness is given by God because we need it; not because we deserve it.
You cannot become righteous by confessing your sins, working for your church, memorizing the 23rd psalm, or keeping the ten commandments. It is not your worthiness, works, or your goodness that makes you right before God. None of us is good enough or strong enough to earn righteousness. We are righteous because God has made us righteous in Christ Jesus.
II Corinthians 5:21
For he [God] hath made him [Jesus Christ] to be sin for us, who knew no sin; that we might be made the righteousness of God in him.
Some Christians teach that a person can be born again, righteous before God, one minute and then do something wrong and become unrighteous. They go on to say that if that person does not work to become righteous again he or she will not be saved and will end up in hell. This is absolutely NOT TRUE! Eternal life is ETERNAL. Saved is Saved. When the spirit of God is born within a believer that person is righteous before God at that moment and forever. It is the nature of God, holy spirit, born within that makes us righteous. It is God's righteousness we receive:
And be found in him, not having mine own righteousness, which is of the law, but that which is through the faith [believing action] of Christ, the righteousness which is of [or from] God by faith [believing].
Even the righteousness of [or from] God which is by faith [believing action] of Jesus Christ unto all and upon all them that believe: for there is no difference:
You cannot be an unrighteous person if you are born again. God has made you righteous, wise, sanctified, and redeemed.
I Corinthians 1:30
But of him [God] are ye in Christ Jesus, who of God is made unto us wisdom, and righteousness, and sanctification, and redemption.
So, if believers have the righteousness of God why do they still live in guilt and condemnation? Why do they still focus on their faults and failures? You can get out of this negative rut by believing what God's Word says about you. There is no fear, worry, fault or failure - God has made you righteous. Simply believe what the Word says and stand. You must change your heart to line up with the Word and then you will have confidence toward God.
I John 3:20-21
For if our heart condemn us, God is greater than our heart, and knoweth all things.
Beloved, if our heart condemn us not, then have we confidence toward God.
So long as your heart (the innermost part of your being) is accusing you and finding fault you cannot have confidence toward God. Even the most simple promises of God become difficult to accept when you are condemning yourself. Line up your thinking with the righteousness that God has given you and you will be able to boldly live with confidence toward God and receive all that He has promised.