When our Lutheran theologians wrote our Confessions, they sat down to their work as true Christians and did not intend to construct a system of doctrine. They knew in what way a poor sinner is given rest and the consolation of salvation. In the Apology, Melanchthon has spoken like a simple Christian. What has made this Confession all the more precious is that he speaks all that he says from the fulness of Scripture and his own experience.
In 1545 an edition of the Latin writings of Luther was published. In the preface to the first part, Luther relates what was the condition of his heart before he had received the light of the Gospel. He makes a personal confession, saying that, while he was in bondage to the Law, he had read the words of the Apostle Paul that the righteousness of God is revealed in the Gospel and had become terrified by that statement. Having been terrified previously by the Law and reading now that in the Gospel, too, the righteousness of God is revealed, he was in an awful dilemma. The Law had condemned him, and now God sent him the Gospel to do the same thing to him! In the Gospel, too, God demanded righteousnes of the sinner!
We cannot sufficiently thank and praise God for giving Luther, shortly before his departure, leisure to relate some of the inner experiences of his life which were to prepare and fit him for the work of the Reformation.
He writes (St. L. Ed. XIV, 446 ff.) : “I verily had a hearty desire, indeed, I was yearning, to understand the Epistle of St. Paul to the Romans. So far nothing had hindered me except only the single phrase justitia Dei [the righteousness of God] in v. 17 of the first chapter, where Paul says: ‘The righteousness of God is revealed in the Gospel.’ I was very wroth at this term ‘righteousness of God’ because my training had been according to the usage and practise of all teachers at that time, and I had been told that I must understand this term after the manner of philosophers as signifying that righteousness by which God is righteous in His essence, does right, and works righteousness, and punishes all sinners and unrighteous persons, — what is called justitia formalis seu activa (essential, or active, righteousness). Now, my condition was this: Although I was leading the life of a holy and blameless monk, I discovered that in the sight of God I was a great sinner. Moreover, my conscience was troubled and distressed, nor did I venture to reconcile God with my own satisfactions and merits. For this reason I did not at all love this righteous and angry God, who punishes sinners, but I hated Him and was full of secret anger against Him, and that, in all seriousness. (I am afraid that this was, or may have to be accounted as, blasphemy.) Frequently I would say: Is God not satisfied with having loaded all manner of misery and affliction, besides the terrors and threatenings of the Law, on us poor, miserable sinners, who are already condemned to everlasting death on account of hereditary sin? Must He increase this misery and heartache still more by the Gospel and by its preaching and its message proclaim His righteousness and serious anger and add to our terror? In my confused conscience I was full of indignation. Nevertheless I continued my meditation on blessed Paul, endeavoring, with a great thirst for knowledge and a hearty desire, to ascertain his meaning in this passage. I spent days and nights in these musings, until by the grace of God I perceived the connection of these words in the passage, thus: The righteousness of God is revealed in the Gospel, as is written: ‘The just shall live by his faith.’ From this connection I learned to understand that righteousness of God by which the righteous lives by the gracious gift of God, through faith alone, and I perceived this to be the apostle’s meaning: By the Gospel that righteousness is revealed which is valid in the sight of God and by which God, from grace and pure mercy, makes us righteous by faith. In Latin this righteousness is called justitia passiva, and to this righteousness the fact refers which says: ‘The just shall live by his faith.’ At this point I immediately felt that I had been entirely born anew and had found a door wide open, leading straight into paradise.”
CFW Walther, Law and Gospel, Twenty-second Evening Lecture (March 13, 1885.