Genesis 7:1“When everything was ready, the Lord said to Noah, “Go into the boat with all your family, for among all the people of the earth, I can see that you alone are righteous.“
This is the first mention of the great doctrine of justification in the Bible–that is, being seen as “righteous” by God.
The same Hebrew word is translated “just” in Genesis 6:9 “This is the account of Noah and his family. Noah was a righteous(Just) man, the only blameless person living on earth at the time, and he walked in close fellowship with God.
The reason Noah was seen as righteous and therefore as just, or justified before God, was that
Genesis 6:8But Noah found favor with the Lord.(grace in the eyes of the LORD).
This is the first mention of “grace” in the Bible.
The first mention of “faith” or “belief” is also associated with justification:
Genesis 15:6“And Abram believed the Lord, and the Lord counted him as righteous because of his faith”.
Thus, in the Old Testament and certainly in the New, justification is by grace through faith.
Romans 3:24“Being justified freely by his grace through the redemption that is in Christ Jesus” and also
Justification–that is, being seen and proclaimed as perfectly righteous, even in spite of past sins–must of course be authorized by God the Creator. “It is God that justifieth” (Romans 8:33). That God can indeed be both “just, and the justifier of him which believeth in Jesus” (Romans 3:26) is based entirely on the substitutionary death and bodily resurrection of Christ who conquered death. “Being now justified by his blood,” the Lord Jesus Christ “was delivered for our offences, and was raised again for our justification” (Romans 5:94:25).
Now, although we are freely justified by grace through faith, such justification inevitably generates good works also, for “by works a man is justified, and not by faith only” (James 2:24).