Some say that justification is a legal act of God in which He declares the sinner to be worthy of heaven even though he continues to be a sinful creature. In this view of justification there is no internal renewal or real sanctification whether instant or through a lifelong process but simply an external application of the justice of Christ.
To Catholic Christians and many other Christians, justification is understood differently. We understand from Scriptures that justification is not the covering of sin but the eradication and the beginning of true sanctification and simultaneous renewal. The soul is transformed into goodness instead of being a sinful soul with sins covered by Christ’s blood. We see Scriptures saying that forgiveness results in a complete removal of sins. The only time the Bible mentions the covering of sin is in the context of one man’s sin being forgiven by another. One should note that we have no power to forgive another’s sin, therefore the context is that we do all we can and cover or overlook those sins against us. In relation to God and His removal of sin the Scriptures use quite different terminology such as “blot out”, “blotting out”, “clears away” and “takes away”.
Catholics see justification as a rebirth and supernatural life in a former sinner:
(Joh 3:5 DRB) Jesus answered: Amen, amen, I say to thee, unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God.
(Tit 3:5 DRB) Not by the works of justice which we have done, but according to his mercy, he saved us, by the laver of regeneration and renovation of the Holy Ghost.
That creates an inner renewal of the soul:
(Eph 4:23 DRB) And be renewed in spirit of your mind:
Resulting in complete sanctification:
(1Co 6:11 DRB) And such some of you were. But you are washed: but you are sanctified: but you are justified: in the name of our Lord Jesus Christ and the Spirit of our God.
Through this glorious process initiated by God’s grace the soul becomes beautiful, holy and worthy of heaven where nothing unclean is allowed. It is not an ugly sinful soul hidden under the blood of Jesus but instead one sanctified by Him and created anew for His glory.