Although not the "formal" cause of the Reformation in the sixteenth century, it ranks close behind the abuse of the sale of indulgences as the cause of it and also one of the things that divides Romanism and Protestantism. Most of us have heard the Latin phrases, sola fide, which simply means "faith alone." The core questions we are asking here relate to how we attain salvation but more specifically within the initial experience of salvation known in theological terms as "justification," the beginning of salvation. Luther began studying and preaching on St. Paul's Epistles before the controversy with John Tetzel culminating in the 95 Theses of 1517. His theological reflection on the book of Romans centered on one central verse which caused him to seriously reflect on Roman teaching at the time. "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). Quoted from Peter Toon's book, Justification and Sanctification, Luther elaborates on his own personal, spiritual quest:
"I greatly longed to understand Paul’s Epistle to the Romans and nothing stood in the way but one expression, “the justice of God,” because I took it to mean that justice whereby God is just and deals justly in punishing the unjust. My situation was that, although an impeccable monk, I stood before God as a sinner troubled in conscience, and I had no confidence that my merit would assuage him. Therefore I did not love a just and angry God, but rather hated and murmured against him. Yet I clung to the dear Paul and had a great yearning to know what he meant.
Night and day I pondered until I saw the connection between the justice of God and the statement that “the just shall live by his faith.” Then I grasped that the justice of God is that righteousness by which through grace and sheer mercy God justifies us through faith. Thereupon I felt myself to be reborn and to have gone through open doors into paradise. The whole of Scripture took on a new meaning, and whereas before the “justice of God” had filled me with hate, now it became to me inexpressibly sweet in great love. This passage of Paul became to me a gate to heaven."
Crutial to Luther's understanding of the justification issue is the state of man after the Fall. "For there is no distinction: for all have sinned and fall short of the glory of God," (Rom. 3:22b,23) "None is righteous, no, not one; no one understands; no one seeks for God" (v. 10,11). We know our problem is grave, "For the mind that is set on the flesh is hostile to God, for it does not submit to God’s law; indeed, it cannot. Those who are in the flesh cannot please God (Romans 8:7-8), "The natural person does not accept the things of the Spirit of God, for they are folly to him, and he is not able to understand them because they are spiritually discerned" (1 Corinthians 2:14), "And you were dead in the trespasses and sins in which you once walked, following the course of this world, following the prince of the power of the air, the spirit that is now at work in the sons of disobedience— among whom we all once lived in the passions of our flesh, carrying out the desires of the body and the mind, and were by nature children of wrath, like the rest of mankind" (Ephesians 2:1-3) and again in, "For we ourselves were once foolish, disobedient, led astray, slaves to various passions and pleasures, passing our days in malice and envy, hated by others and hating one another" (Titus 3:3) and this problem has no remedy which we can find in ourselves. What then are to we di in such a predicament? This is the key of the Gospel, the Good News of God in Christ, proclaimed to us in the pages of the New Testament. As Romans 3:23 proclaims, "for all have sinned and fall short of the glory of God," however, the Apostle does not stop there! The rest of the verse reads, "and are justified by his grace as a gift, through the redemption that is in Christ Jesus, whom God put forward as a propitiation by his blood, to be received by faith" (Romans 3:24,25). "For the wages of sin is death," however, God does not leave us to damnation from our sins, no, he freely saves for, "the free gift of God is eternal life in Christ Jesus our Lord" (Romans 6:23). "God shows his love for us in that while we were still sinners, Christ died for us" (Romans 5:8).
The biblical doctrine of justification by faith is something which cannot be compromised or misunderstood. The Council of Trent in the latter part of the 16th century refuted the clear Protestant and biblical teaching on justification on every point. Beginning with the formal cause of justification, the council declared, “the alone formal cause is the justice of God, not that whereby He Himself is just, but that whereby He maketh us just, that, to wit, with which we being endowed by Him, are renewed in the spirit of our mind, and we are not only reputed, but are truly called, and are, just, receiving justice within us, each one according to his own measure, which the Holy Ghost distributes to every one as He wills, and according to each one's proper disposition and co-operation.” This is often called infused righteousness in opposition to the biblical concept of imputed righteousness which was the formal cause of justification according to the Reformers. “they are righteous because they believe in Christ, whose righteousness covers them and is imputed to them.”
The Council of Trent then explains the Roman understanding of what is the instrumental cause of justification which is, “is the sacrament of baptism, which is the sacrament of faith, without which (faith) no man was ever justified,” another spit in the face of Reformation theology. Biblical theology allows faith alone as the instrument of justification (some Protestants allow that baptism is the instrument of regeneration but not justification). Luther says, “Faith, however, is something that God effects in us. It changes us and we are reborn from God, John 1:13. Faith puts the old Adam to death and makes us quite different men in heart, in mind, and in all our powers; and it is accompanied by the Holy Spirit. O, when it comes to faith, what a living, creative, active, powerful thing it is. It cannot do other than good at all times. It never waits to ask whether there is some good work to do; rather, before the question is raised, it has done the deed, and keeps on doing it. A man not active in this way is a man without faith. He is groping about for faith and searching for good works, but knows neither what faith is nor what good works are. Nevertheless, he keeps on talking nonsense about faith and good works.”
The last point with which biblical theology departs from Tridentine theology is in the relation between the justified and their sin nature. Trent says that a justified sinner is completely free from the stains of original sins, however, Luther states something entirely different. While on earth the sinner is simultaneously sinful and just (simul iustus et peccator). Peter Toon says this, “While on earth, the position of the Christian does not change. He is totally righteous through faith, and he remains always and completely a sinner. With reference to Christ he is righteous; but with reference to his fallen nature he is sinful. Yet this apparent contradiction does not imply a static situation. The very faith that draws Christ into the heart and creates the new nature gladly and freely allows Christ to do battle against the old, sinful nature (= “the flesh”). The result of this spiritual conflict (described by St. Paul in Romans 7, 8) should be that “Christ is constantly formed in us and we are formed according to his own image.”12 Each and every day faith is to grasp anew the word of promise which is the gospel and appropriate Christ, who is our righteousness. Further, each and every day sin, the devil and temptation must be fought. Yet despite all the daily battles, the old nature remains with us until death. There is no escape from it, nor from the possibility of sin. So Luther has no doctrine of progressive holiness or growth in sanctification (as these terms were later used). The flesh or old nature does not change; rather, Christ (or really the new nature) grows within the believer. Justification includes the daily renewal of the new nature. The believer can never say he is less sinful than he was at any earlier time!”