The Great Controversy, by Ellen G. White, , at sacred-texts.com
But notwithstanding all the persecution and the putting to death of the saints, yet living witnesses were raised up on every hand. The angels of God were doing the work committed to their trust. They were searching in the darkest places, and were selecting out of the darkness, men who were honest at heart. They were all buried up in error, yet God selected them as he did Saul, as chosen vessels to bear his truth, and raise their voices against the sins of his professed people. The angels of God moved upon Martin Luther, Melancthon, and others in different places, to thirst for the living testimony of the word of God. The enemy had come in like a flood, and the standard must be raised up against him. Luther was chosen to breast the storm, and stand up against the ire of a fallen church, and strengthen the few who were faithful to their holy profession. He was ever fearful of offending God. He tried through works to obtain the favor of God; but he was not satisfied until a gleam of light from heaven drove the darkness from his mind, and led him to trust, not in works, but in the merits of the blood of Christ; and to come to God for himself, not through popes nor confessors, but through Jesus Christ alone. O how precious was this knowledge to Luther! He prized this new and precious light which had dawned upon his dark understanding, and had driven away his superstition, higher than the richest earthly treasure. The word of God was new. Every thing was changed. The Book he had dreaded because he could not see beauty in it, was life, LIFE to him. It was his joy, his consolation, his blessed teacher. Nothing could induce him to leave its study. He had feared death; but as he read the word of God, all his terrors disappeared, and he admired the character of God, and loved him. He searched the word of God for himself. He feasted upon the rich treasures it contained, and then he searched it for the church. He was disgusted with the sins of those in whom he had trusted for salvation. He saw very many enshrouded in the same darkness which had covered him. He anxiously sought an opportunity to point them to the Lamb of God, who alone taketh away the sin of the world. He raised his voice against the errors and sins of the Papal church, and earnestly longed to break the chain of darkness which was confining thousands, and causing them to trust in works for salvation. He longed to be enabled to open to their minds the true riches of the grace of God, and the excellence of salvation obtained through Jesus Christ. He raised his voice zealously, and in the power of the Holy Spirit, cried against the existing sins of the leaders of the church; and as he met the storm of opposition from the priests, his courage did not fail; for he firmly relied upon the strong arm of God, and confidently trusted in him for victory. And as he pushed the battle closer and closer, the rage of the priests was kindled against him. They did not wish to be reformed. They chose to be left in ease, in wanton pleasure, in wickedness. They wished the church kept in darkness.
I saw that Luther was ardent and zealous, fearless and bold in reproving sin, and advocating the truth. He cared not for wicked men and devils. He knew that he had One with him mightier than they all. Luther possessed fire, zeal, courage and boldness, and at times might go too far; but God raised up Melancthon, who was just the opposite in character, to aid Luther, and carry on the work of reformation. Melancthon was timid, fearful, cautious, and possessed great patience. He was greatly beloved of God. His knowledge was great in the Scriptures, and his judgment and wisdom was excellent. His love for the cause of God was equal to Luther's. These hearts, the Lord knit together; they were friends which were never to be separated. Luther was a great help to Melancthon when he was in danger of being fearful and slow, and Melancthon was also a great help to Luther to keep him from moving too fast. Melancthon's far-seeing cautiousness often averted trouble which would have come upon the cause, if the work had been left alone to Luther; and the work would often have failed in being pushed forward, if it had been left to Melancthon alone. I was shown the wisdom of God in choosing these two men, of different characters to carry on the work of reformation.
I was then carried back to the days of the apostles, and saw that God chose as companions an ardent and zealous Peter, and a mild, patient, meek John. Sometimes Peter was impetuous. And the beloved disciple often checked Peter, when his zeal and ardor led him too far; but it did not reform him. But after Peter had denied his Lord, and repented, and was converted, all he needed was a mild caution from John to check his ardor and zeal. The cause of Christ would often have suffered had it been left alone to John. Peter's zeal was needed. His boldness and energy often delivered them from difficulty, and silenced their enemies. John was winning. He gained many to the cause of Christ by his patient forbearance, and deep devotedness.
God raised up men to cry against the existing sins of the Papal church, and carry forward the reformation. Satan sought to destroy these living witnesses; but God made a hedge about them. Some, for the glory of his name, were permitted to seal the testimony they had borne with their blood; but there were other powerful men, like Luther and Melancthon, who could best glorify God by living and crying aloud against the sins of popes, priests and kings. They trembled before the voice of Luther. Through those chosen men, rays of light began to scatter the darkness, and very many joyfully received the light and walked in it. And when one witness was slain, two or more were raised up to fill his place.
But Satan was not satisfied. He could only have power over the body. He could not make believers yield their faith and hope. And even in death they triumphed with a bright hope of immortality at the resurrection of the just. They had more than mortal energy. They dared not sleep for a moment. They kept the Christian armor girded about them, prepared for a conflict, not merely with spiritual foes, but with Satan in the form of men, whose constant cry was, Give up your faith, or die. Those few Christians were strong in God, and more precious in his sight than half a world bearing the name of Christ, yet cowards in his cause. While the church was persecuted, they were united and loving. They were strong in God. Sinners were not permitted to unite themselves with it; neither the deceiver nor the deceived. Those only who were willing to forsake all for Christ could be his disciples. They loved to be poor, humble and Christ-like.
See Luke 22:61-62; John 18:10; Acts chap. 3 & 4
For further study see "The Reformation" in an encyclopedia.