The Diet of Worms was the trial of Martin Luther for being a heretic. His writings were critical of the Roman Church’s obscuring the Biblical message of the gospel. Luther was convinced the Bible was to be the sole authority of the Church, not popes or councils of men. Luther's chief concern was bringing the Scriptural teaching of justification by faith in Christ alone back to light.
Luther was initially called upon to look at a table full of his books and retract what he wrote therein. His opposition to papal authority was the root matter that angered Rome and the chief charge they demanded Luther answer. After a day of questioning Luther requested more time to consider his answer to their demand for recantation. In his excellent "History of the Reformation in the Sixteenth Century", historian J.H. Merle D'Aubigne narrates one of the greatest events in the history of the Church:
At the beginning of the next day, the orator of the diet, said indignantly: “You have not answered the question put to you. You were not summoned hither to call in question the decisions of councils. you are required to give a clear and precise answer. Will you, or will you not, retract?”
Upon this Luther replied without much hesitation: “Since your most serene majesty and your high mightinesses require from me a clear, simple, and precise answer, I will give you one, and it is this: I cannot submit my faith either to the pope or to the councils, because it is clear as the day that they have frequently erred and contradicted each other. Unless therefore I am convinced by the testimony of Scripture, or by the clearest reasoning, — unless I am persuaded by means of the passages I have quoted, — and unless they thus render my conscience bound by the Word of God, I cannot and I will not retract, for it is unsafe for a Christian to speak against his conscience.” And then, looking round on this assembly before which he stood, and which held his life in its hands, he said: “HERE I STAND, I CAN DO NO OTHER; MAY GOD HELP ME? AMEN!”
Luther, constrained to obey his faith, led by his conscience to death, impelled by the noblest necessity, the slave of his belief, and under this slavery still supremely free, like the ship tossed by a violent tempest, and which, to save that which is more precious than itself, runs and is dashed upon the rocks, thus uttered these sublime words which still thrill our hearts at an interval of four centuries: thus spoke a monk before the emperor and the mighty ones of the nation; and this feeble and despised man, alone, but relying on the grace of the Most High, appeared greater and mightier than them all. His words contain a power against which all these mighty rulers can do nothing. This is the weakness of God, which is stronger than man. The empire and the Church on the one hand, this obscure man on the other, had met. God had brought together these kings and these prelates publicly to confound their wisdom. The battle is lost, and the consequences of this defeat of the great ones of the earth will be felt among every nation and in every age to the end of time.
The assembly was thunderstruck. Many of the princes found it difficult to conceal their admiration. The emperor, recovering from his first impression, exclaimed: “This monk speaks with an intrepid heart and unshaken courage.” The Spaniards and Italians alone felt confounded, and soon began to ridicule a greatness of soul which they could not comprehend.
“If you do not retract,” said the chancellor, as soon as the diet had recovered from the impression produced by Luther’s speech, “the emperor and the states of the empire will consult what course to adopt against an incorrigible heretic.” At these words Luther’s friends began to tremble; but the monk repeated: “May God be my helper; for I can retract nothing.”
After this Luther withdrew, and the princes deliberated. Each one felt that this was a critical moment for Christendom. The yes or the no of this monk would decide, perhaps for ages, the repose of the Church and of the world. His adversaries had endeavored to alarm him, and they had only exalted him before the nation; they had thought to give greater publicity to his defeat, and they had but increased the glory of his victory.