On April 18, 1517, Martin Luther reappeared before the Diet of Worms, having spent the previous night agonizing over how to respond, and had this exchange with his examiner, Johann Eck:
ECK: Martin, how can you assume that you are the only one to understand the sense of Scripture? Would you put your judgment above that of so many famous men and claim that you know more than they all?
You have no right to call into question the most holy orthodox faith, instituted by Christ the perfect law-giver, proclaimed throughout the world by the apostles, sealed by the red blood of the martyrs, confirmed by the sacred councils, defined by the Church in which all our fathers believed until death and gave to us as an inheritance, and which now we are forbidden by the pope and the emperor to discuss lest there be no end of debate.
I ask you, Martin—answer candidly and without horns—do you or do you not repudiate your books and the errors which they contain?
LUTHER: Since then Your Majesty and your lordships desire a simple reply, I will answer without horns and without teeth. Unless I am convicted by Scripture and plain reason—I do not accept the authority of popes and councils, for they have contradicted each other—my conscience is captive to the Word of God.
I cannot and I will not recant anything, for to go against conscience is neither right nor safe. God help me. Amen.
(Quotation in Roland H. Baiton’s book Here I Stand a Life of Martin Luther
HT: Desiring God, @c_larson