It was one of the most important moments in Christian history – the day it dawned on Martin Luther that he had been wrong. It’s not as though Martin had never read the Book of Romans or heard of Paul’s statements regarding being right with God, its that his eyes had never been opened by the Holy Spirit to see HOW a person is made right with God… until that particular day when he read:
For in it the righteousness of God is revealed from faith for faith, as it is written, “The righteous shall live by faith.”Romans 1:17
As Luther explains: “Then finally God had mercy on me, and I began to understand that the righteousness of God is a gift of God by which a righteous man lives, namely faith, and that sentence: The righteousness of God is revealed in the Gospel, is passive, indicating that the merciful God justifies us by faith, as it is written: ‘The righteous shall live by faith.’ Now I felt as though I had been reborn altogether and had entered Paradise. In the same moment, the face of the whole of Scripture became apparent to me. My mind ran through the Scriptures, as far as I was able to recollect them, seeking analogies in other phrases, such as the work of God, by which He makes us strong, the wisdom of God, by which He makes us wise, the strength of God, the salvation of God, the glory of God. Just as intensely as I had now hated the expression ‘the righteousness of God,’ I now lovingly praised this most pleasant word. This passage from Paul became to me the very gate to Paradise.” 
Why the Wonder?
The prevailing teaching of the Roman Catholic Church was “infused grace,” or “process justification” (see Part 1) which means that God’s grace flows to the sinner so that he might become righteous. Therefore, the life of Luther and the very notion of faith was heavily focused upon obedience and behavior. Essentially, the Roman Catholic Church taught that our righteousness was a gradual process in which the sinner starts to become righteous as God creates a new will in a person so that he or she begins to fulfill the Law. At best, the grace of God to a Roman Catholic makes salvation a possibility, never a certainty. In the end, God will decide how the person has used the gift of grace that was available to them as they stand before Him.
What does the Bible say?
The discovery of Luther – that his own works, behavior, or obedience could never determine his standing before God was fueled by the teaching of the Apostle Paul: For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin (Romans 3:20) and illustrated in the life of Abraham: For if Abraham was justified by works, he has something to boast about, but not before God. 3 For what does the Scripture say? “Abraham believed God, and it was counted to him as righteousness (Romans 4:2–3). The notion of cooperating with God, as taught by the RCC, had no possibility of even beginning within a person since our spiritual depravity leaves us completely unable to move toward God: It is written, none is righteous, no, not one; 11 no one understands; no one seeks for God (Romans 3:10-11). Therefore, it must be the mighty working of grace alone that produces life, and the righteousness we receive must be based on the merits of Christ alone and received by faith alone.
Transformed by the Gospel
When Luther discovered that he is declared righteous by God on the basis of placing his faith for salvation in the saving work of Christ alone, he was transformed: “These words ‘righteous’ and ‘righteousness of God’ struck my conscience as flashes of lightning, frightening me each time I heard them: if God is righteous, he punishes. But by the grace of God, as I once meditated upon these words in the tower: ‘The righteous shall live by faith’ and ‘the righteousness of God,’ there suddenly came into my mind the thought that if we as righteous are to live by faith, and if the righteousness of faith is to be for salvation to everyone who believes, then it is not our merit, but the mercy of God. Thus my soul was refreshed, for it was the righteousness of God by which we are justified and saved through Christ.” 
What did the Roman Catholic Church say?
The Roman Catholic Church studied the teaching of Luther and the other reformers for 18 years. Then, in the Council of Trent (1545-1553), the leaders of the Roman Catholic Church met for the purpose of countering the teaching of the Reformation. The following quotes come from the sixth session of the Council meeting and stand to this day as the official position of the Roman Catholic Church toward anyone who believes in salvation by grace alone through faith alone solely based on the merits of Christ alone.
Canon 8: “When the apostle says that a person is justified by faith and as a gift, those words are to be understood in the sense which the perennial consent of the catholic church has maintained and expressed, namely, that we are said to be justified by faith because faith is the first stage of human salvation, the foundation, and root of all justification, without which it is impossible to please God and come to fellowship of his children.”
Canon 9: “If anyone says that the sinner is justified by faith alone, meaning thereby that no cooperation is required for him to obtain the grace of justification, and that in no sense is it necessary for him to make preparation and be disposed of by a movement of his own will; let him be anathema.”
Canon 10: “…Through the observance of the commandments of God and of the Church, faith cooperating with good works, increase in that justice received through the grace of Christ and are furthered justified…”
Canon 12: “If anyone says that the faith which justifies is nothing else but trust in the divine mercy, which pardons sins because of Christ; or that it is that trust alone by which we are justified; let him be anathema.”
Canon 24: If anyone says that the justice received is not preserved and also not increased before God through good works, but that those works are merely the fruits and signs of justification obtained, but not the cause of its increase, let him be anathema.
Canon 32: “If anyone says that …the justified person, by the good deeds done by him through the grace of God and the merits of Jesus Christ (of whom he is a living member), does not truly merit an increase in grace… let him e anathema.”
The council closed with the following battle cry directed toward any and all protesting (a.k.a “Protestant”) groups:
Canon 33: If anyone says that the Catholic doctrine of justification as set forth by the Holy Council and the present degree, derogates in some respect from the glory of God or the merits of our Lord Jesus Christ, let him be anathema.
There Really is a Difference
While some may like to think that Roman Catholic teaching and Protestant teaching are merely different branches rooted in the same tree of faith, notice the word “anathema” used in the formal pronouncement on the teaching of Luther and the Reformers in the conclusions by the Council. “Anathema” means “accursed” or “damned.” In other words, if a person believes what the Reformation teaches then that individual is under the curse of God.
The distinction in teaching how a person can be saved from sin could not be more obvious. The distinction between the Roman Catholic Church and the Reformers is analogous to not only being two distinct “trees” but two different trees in completely different orchards. The Roman Catholic Church designates anyone who trusts in the merits of Christ alone based on faith alone as being under the curse of God. Now you know the difference between Catholics and Protestants.
- Oberman, Heiko A. Luther: Man between God and the Devil. Yale University Press, 2006. Pg. 183-185
- Saarnivaara, Uuras. Luther Discovers the Gospel: New Light upon Luther’s Way from Medieval Catholicism to Evangelical Faith. St. Louis, MO : Concordia Publishing House, 2005. pg. 37