RIGHTEOUSNESS means the following in various senses:
•Purity of heart and rectitude of life; conformity of heart and life to the divine law. Righteousness, as used in Scripture and theology, in which it is chiefly used, is nearly equivalent to holiness, comprehending holy principles and affections of heart, and conformity of life to the divine law. It includes all we call justice, honesty and virtue, with holy affections; in short, it is true religion.
• Applied to God, the perfection or holiness of his nature; exact rectitude; faithfulness.
• The active and passive obedience of Christ, by which the law of God is fulfilled. Dan 9.
From mine perspective righteousness is having purity as your essence. Being RIGHT,without wrong or impurity before God.
How do we become righteous?
One becomes righteous through faith in Christ Jesus.(ROM 4:3)
You ought to believe in Christ Jesus and accept Him into your body to rule over you.Christ became sin on the cross that we may have His righteousness (His life),so it was an exchange on the cross,He paid the price for sin; which is death on a cross;and cursed is one who us hung on a tree (cross) such did Jesus become for our sake.He died and resurrected that we may receive and posses life and have it abundantly as we believe in Him ||ROM 10:4||.
When God gave Moses the law,they could never fully obey it,because when they break one they became guilty of all. So God sent His Son down,to fulfill the law so we can do same. So the law was summarized and fulfilled by Christ as LOVE; love your neighbour as I have loved you. Christ lived the example and empowered us to do so by giving us His Holy Spirit.
By such an act of Christ on earth His nature is imputed on everyone who believes and embraces Him. His blood washes us and makes us CLEAN ,without fault or sin.
So then by default we become righteous through faith in Christ Jesus(who is the life of God) 2Cor 5:21,Rom 3:20-22.Then if Christ be in you and you in God it means you become the righteousness of God in Christ Jesus.
So in a nutshell we do not need the law of Moses to become righteous but the grace of God by which we receive the life of CHRIST and this life empowers us to do one thing, love; in deed,in word and in sense>|.
End note :
KJV:Being justified freely by his grace through the redemption that is in Christ Jesus Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God;
To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.Where is boasting then? It is excluded. By what law? of works? Nay: but by the law of faith.Therefore we conclude that a man is justified by faith without the deeds of the law.
Go Deeper :
Romans 1:17, 3,8,10:3.
Live the life of faith,you ain’t a slave to sin.😋