Review the following Video for background:
The Just Shall Live by Faith Alone | Martin Luther

2 days from now on October 31, 2017 is the 500th anniversary of a very significant moment in church history.   But it is very unlikely that you will hear anything about this anniversary in the news.  It is more likely that you will see people dressed up for Halloween.  People will hustle and bustle to prepare for the Halloween “holiday.”  And recognition of this event will pass largely unnoticed.  But the event that happened 500 years ago this Tuesday unleashed a chain of events that rocked the civilized world and continues to reverberate today. 
500 years ago on October 31, 1517, a Roman Catholic priest named Martin Luther took a long scroll of paper with 95 statements or claims on it.  He went to the church door in the village called Wittenberg, Germany.  There he nailed the paper to the door.  The posting of this paper was not unusual for the church door served as a kind of public notice board.  It was the 95 claims that mattered.  They confronted common practices in the church that day and criticized the pope. His paper was soon copied and spread throughout the German speaking world. 
What led Martin Luther to do this?