Brady Adler

“Luther came to the conclusion that the “justice of God” does not refer, as he had been taught, to the punishment of sinners. It means rather that the “justice” or “righteousness” of the righteous is not their own, but God’s. The “righteousness of God” is that which is given to those who live by faith. It is given, not because they are righteous, nor because they fulfill the demands of divine justice, but simply because God wishes to give it. Thus, Luther’s doctrine of “justification by faith” does not mean that what God demands of us is faith, as if this were something we have to do or achieve, and which God then rewards. It means rather that both faith and justification are the work of God, a free gift to sinners. As a result of this discovery, Luther tells us, “I felt that I had been born anew and that the gates of heaven had been opened. The whole of Scripture gained a new meaning. And from that point on the phrase ‘the justice of God’ no longer filled me with hatred, but rather became unspeakably sweet by virtue of a great love.”
― Justo L. González, The Story of Christianity: Volume 2: The Reformation to the Present Day