By Dr. John Pappas
Bible Greek Vpod
Q. Dr. Pappas, I heard you say a saved person is declared righteous. How can a person be righteous?
A. To be declared righteous is a forensic pronouncement. The word forensic is from the Latin meaning, "relating to the business of the Roman forum." The Roman forum is where the legal dealings were pronounced. A criminal charge was presented to the public in the forum, the case and the arguments were presented, and the outcome was pronounced. When a person is saved he or she is declared righteous based not on what they have done, but rather, on the work of Christ on the cross and His righteousness is reckoned to us. This reckoning is called imputation. Imputation comes from the Greek ellogeo meaning "to reckon over to one’s account" (eg. Rom. 5:13).
The 3 Great Imputations
There are three great imputations in Scripture:
- The imputation of Adam’s sin to the human race (Rom. 5:12-21). Here, death has been declared as the penalty upon all men in that all have sinned, meaning all men sinned when Adam sinned, and thus, the penalty of death is upon all mankind because of one sin of Adam (Rom. 5:18). Romans 5:12 says that all humanity was a participant in Adam’s sin. How is it that you and I participated in Adam’s sin, we were not there! We participated in Adam’s sin because we were "seminally present." "Just like Levi (although not yet born) paid tithes to Melchizedek through Abraham in that Levi was 'seminally present' in Abraham (Heb. 7:9-10)"  Seminally present means present by means of the seeds or offspring.
- The imputation of the sin of the race to Christ. Though the word imputation is not found here, it is no less understood by words such as "made him to be sin," "laid on him," "bare our sins"  The imputation of the sin of the race upon Jesus Christ occurred at the cross.
- The imputation of the righteousness of Christ to believers. The imputation of Christ’s righteousness to believers constitutes our legal standing before God. "It is the only righteousness that God ever accepts for salvation and by it alone may one enter heaven"  Righteousness is the Greek word dikaioo meaning "justify, be righteous, be freed, to declare or pronounce one to be just or righteous." Both the Old and New Testament use the word in a legal sense.
The concept of justification or righteousness as a legal term goes back to the Old Testament as the Greek LXX uses the word for the court and the decisions of the judges in Deut. 25:1, "If there is a dispute between men, and they come to court, that [the judges] may judge them, and they justify the righteous and condemn the wicked," (cf., 1 Kings 8:32; Prov. 17:15; Isa. 5:23)
Justification is what God brings to mankind in both the Old and New Testaments. Notice what Isaiah says,
"I bring My righteousness near, it shall not be far off; My salvation shall not linger. And I will place salvation in Zion, for Israel My glory" (Isa. 46:13).
However, the basis of our justification is Jesus Christ as Isaiah declares, "He shall see the labor of His soul, and be satisfied. By His knowledge My righteous Servant shall justify many, for He shall bear their iniquities" (Isa. 53:11), and "...their righteousness [is] from Me, says the Lord" (Isa. 54:17). One of the most popular verses used to described this concept comes from Isaiah 61:10,
"I will greatly rejoice in the Lord, my soul shall be joyful in my God; For He has clothed me with the garments of salvation, He has wrapped me with the robe of righteousness".
In order to see the New Testament declaration, one need only turn to Paul in Romans 8:33-34,
"Who will bring a charge against God’s elect? God is the one who justifies; who is the one who condemns? It is Christ who died, and furthermore is also risen, who is even at the right hand of God, who also makes intercession for us."
Justification or being declared righteous is not a process, but is an act of God when a person places his or her faith in Jesus Christ as their Savior. The act of being declared righteous is clearly described in the past tense as Paul writes in Titus 3:7, "that having been justified by His grace, we should become heirs according to the hope of eternal life." Again, in Romans 5:1, "Therefore having been justified by faith, we have peace with God through our Lord Jesus Christ." (cf. Rom. 5:9; Gal. 3:8-9)
What about the present tense usage of the word "to justify?" One verse that Catholics use to justify their doctrine of man achieving "progressive righteousness" is Romans 3:28, "Therefore we conclude that a man is justified by faith apart from the deeds of the law," which means, not "becomes more righteous," but "a man with faith is in the present declared righteous." 
This doctrine is of most importance since it affects the person of Christ—If a man can achieve righteousness, even if it is said that a man can simply contribute, or add to his or her righteousness, then Christ is not wholly man and wholly God. There is only one who could pay the price for mankind and that one is Jesus Christ the perfect Lamb of God who takes away the sin of the world. Justification means, "being declared righteous" and any other definition is not only inconsistent with the historical usage of the word, but ultimately means man is capable of self-righteousness, and who wants to claim that?