Today's date has significance for Christianity.
The Pope.
Martin Luther.
The Reformation.
July 16, 1519: The Disputation of Leipzig, in which Martin Luther argued that church councils had been wrong and that the church did not have ultimate doctrinal authority, ends.
https://www.christianitytoday.com/history/today/july-16.html
Luther’s use of Scripture to challenge the pope came to a climax in the early summer of 1519 when Luther and the renowned theologian John Eck met face to face in Leipzig to debate the main topics of contention raised by the Wittenberg theologians. The debate wouldn’t have been such a big deal. In fact, after the debate, Eck admitted that he was willing to concede to Luther on 12 of the 13 theses. But the fact that the pope and his authority was challenged raised the stakes. Men had been branded heretics and executed for less.
No matter how accurately Luther argued from the Scriptures, Eck seemed to have the crowd in his hand. The citizens and students at Leipzig never wavered in their support. When the proceedings of the debate were submitted to the two sets of judges, the theologians of Paris decided in Eck’s favor and Erfurt was silent.
This would be defeat from a human or worldly perspective. But from the perspective of God and his angels, the first major battle of the Reformation had been a resounding victory. The Scriptures had come to the fore, and they would not be silenced by Eck, the pope, or any other man.
https://lutheranreformation.org/history/the-leipzig-debate/