Luther saw right through this by way of a (re)discovery of two all-important truths. The first concerns sin. The problem is not sins, as in the quantity. The true problem is that I am a sinner at the root (radix in Latin). I am a sinner and God is holy. This explains why Luther sometimes declared that he hated God. God, the righteous judge, demands righteousness. Yet, I can never achieve righteousness because I am a sinner at the root.
The second all-important truth may be summed up in the expression alien righteousness. The righteousness God demands was earned apart from me and entirely apart from any works I might do even when enabled by grace. This righteousness was earned by Christ alone. It is outside of me, or alien to me.
Theologians use the word imputation. That means that my sin—not the part but the whole—is imputed to Christ. He takes my sin upon Him at the cross and, as my substitute, endures the cup of God’s wrath. Then Christ’s righteousness is imputed to me. His perfect obedience is counted as mine, and I am declared righteous. This is the gospel.
The question is, where did Luther learn this? He learned it from reading the Bible, from reading in Habakkuk that the righteous shall live by faith (Hab. 2:4). He learned it from reading Romans and Galatians. From 1515 through 1520, Luther was lecturing on these particular books. He was immersed in the text.
Luther’s reading of the Bible is at the heart of his contest with the false church of his day. It led him to post the Ninety-Five Theses at Wittenberg on October 31, 1517. Desiderius Erasmus, the humanist scholar, published the Greek text of the New Testament in 1516. Luther was reading it when he was formulating his theses.
When Luther debated Eck at Leipzig, he clearly laid down the Reformation plank of sola Scriptura. At Worms in 1521, he stood upon Scripture. “My conscience is captive to the Word of God,” he thundered. He was convinced that Scripture alone is the church’s final authority.
From 1521 until his death in 1546, Luther labored to see the church firmly established upon the Word of God and boldly proclaiming salvation in the finished work of Christ alone by grace alone through faith alone. Luther’s words at Torgau in 1544 marked his entire ministry: “We can spare everything except the Word.”