Biblical words for "imputation" and "justification" refer to God's objective work, not subjective, internal, progressive moral reformation within man

"The true import of the word 'justify' seems to have been corrupted among the Romanists, when the Latin Vulgate alone was taken as the guide; for the Latin word, from which our English term is derived, taken aside from its use seems to carry with it the signification, not of declaring, but making a man just; but in the original terms, both in the Hebrew and Greek, there is no ambiguity. The words express uniformly the sense which we have put on them; that is, they mean, to account, to esteem, to declare a person to be just or righteous, and never to make a man just or righteous by the infusion of grace. Justification and Sanctification should, therefore, be carefully distinguished, although they should never be separated. The difference between these two benefits which arise from union with Christ, is well expressed in the answer to the 77th Question, in our Larger Catechism. 'Although sanctification be inseparably joined with justification, yet they differ, in that, God in justification imputeth the righteousness of Christ, in sanctification his Spirit infuses grace, and enableth the exercise thereof: in the former, sin is pardoned, in the other, it is subdued: the one doth equally free all believers from the avenging wrath of God, and that perfectly in this life, that they never fall into condemnation: the other is neither equal in all, nor in this life perfect in any, but growing up to perfection." (Archibald Alexander, “A Treatise on Justification by Faith Alone”)


"To inquire what is meant by the imputation of this righteousness; which is the way in which it becomes ours and indeed is the only way in which it can become ours. The Hebrew word כשח in Genesis 15:6 and the Greek word logizwmai used by the apostle here, signifies to estimate, reckon, impute, or place something to the account of another. So the righteousness of Christ is estimated, reckoned, and imputed to be his people's, and is placed to their account as such by God the Father, and looked upon as much by him as their justifying righteousness or as though it had been wrought by them, in their own persons. That this righteousness becomes ours this way, is manifest. For in the same way that Adam's sin became ours, the same way the righteousness of Christ becomes ours; or the same way we are made sinners by the disobedience of Adam, are we made righteous by the obedience of Christ (Rom. 5:19). For as by one man's disobedience, many were made sinners. So by the obedience of one, shall many be made righteous. Now Adam's sin became ours, or we were made sinners, through his sin; by imputation, it was reckoned, it was placed to the account of all his posterity. So Christ's righteousness becomes ours, or we are made righteous, through that righteousness of his; by the imputation of it to us, it is reckoned, it is placed to our account. Again, the same way our sins became Christ's, Christ's righteousness becomes ours, as appears from 1 Corinthians 5:21. He who knew no sin, was made sin for us, that we might be made the righteousness of God in him. Now the way in which Christ was made sin for us, was by imputation; he never had any sin inherent in him, though he had it transferred unto him and laid upon him. So the way in which we are made the righteousness of God, must be by the imputation of Christ's righteousness, and indeed we cannot be made righteous any other way, than by imputation. For the objects of justification are ungodly persons in themselves; for God justifies the ungodly, as in the verse preceding my text. Now if they are ungodly in themselves, then they are not justified by a righteousness of their own, it must be by the righteousness of another. And if they are justified by the righteousness of another, that other's righteousness must be some way or other made theirs, it must be placed to their account, and reckoned as their own, which is only done by an imputation of it to them." (John Gill, "The DOCTRINE OF IMPUTED RIGHTEOUSNESS Without Works Asserted And Proved")


“I may also remind you that Augustine, and a few of the other fathers, misled by this etymology, and their ignorance of Greek, conceived and spoke of justification as a change of moral state, as well as of legal condition. Here is the poisonous germ of the erroneous doctrine of the Scholastics and of Trent concerning it; a striking illustration of the high necessity of Hebrew and Greek literature, in the teachers of the Church.” (R.L. Dabney, “Systematic Theology”)