That's a very good question. I maintain there were always a core set of people in the western church that understood the concept of unmerited grace. Some of our Orthodox and Catholic friends would say this isn't so, that Luther invented the whole thing. However the Reformation wasn't isolated to Germany but was happening in Eastern Europe (Tynsdale), England (Wycliff), Switzerland (Ziggy???), and Spain (Queen Isabella)-yes her too. It just took someone (in this case Luther) to finally say, "Enough" to the Church to start the ball rolling.
But let's assume for a moment that no one understood the grace of God. I would refer back to King Josiah when Judah found the writings sealed in a room within the temple during renovations. The scriptures tells us that when the books were opened and read, the people wept.
How did Judah know it was really God's writings? They hadn't heard it for centuries. That, is simply the power of the word of God. There are moments of great darkness and moments of great illumination.
Yes, the core set of people were Catholics (and by this term I include the Orthodox). Luther didn't invent unmerited grace. From the Cathechism of the Catholic Church:
1996 Our justification comes from the grace of God. Grace is favor, the free and undeserved help that God gives us to respond to his call to become children of God, adoptive sons, partakers of the divine nature and of eternal life.
Free and unmerited.
"I would refer back to King Josiah when Judah found the writings sealed in a room within the temple during renovations. The scriptures tells us that when the books were opened and read, the people wept.
How did Judah know it was really God's writings? They hadn't heard it for centuries. That, is simply the power of the word of God. There are moments of great darkness and moments of great illumination."
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Great point. I had forgotten this event. As always the answer can be found in SCRIPTURE.