Reformation Dayis aProtestantChristianreligious holiday celebrated on31 October.
On October 31, 1517 was the dayGermanmonkMartin Luthernailed hisNinety-five Theseson the door of theAll Saints’ ChurchinWittenberg,Electorate of Saxonyin theHoly Roman Empire.
Prayer A to Z 
Yes, Happy Reformation Day! It’s been 504 years since Dr. Luther used his hammer on the door of the Wittenberg church. Soon afterwards he had a showdown with Emperor Charles V (in April of A.D.1521), and the Protestant Reformation rocketed forward. On this day, 500 years ago (A.D.2021), Dr. Luther was busy translating the Holy Bible in German, hidden inside the Wartburg Castle (with Erasmus’ Greek New Testament, pen, ink, good German food, etc.), prudently using the pretended identity of “Junker Jorg” (Knight George). In time Dr. Luther emerged back into the public life in Germany, with a German translation of the Holy Bible for folks to read in their mother tongue. Thank God for the Protestant Reformation!
Thanks James for that information.