One of Luther’s main disagreements he had with the Catholic Church is that money was required for salvation. As in you had to give money to the church to go to Heaven.
There was also many poor people, but they were required to give money to the church because they thought it was necessary to be saved, but the church leaders were very rich.
So the first answer would be:
THE ACCUMULATION OF WEALTH BY CHURCH OFFICIALS
One of the other main issues that Martin Luther had with the Catholic Church was about indulgences. Indulgences we’re prices of paper that if you bought them, you would spend less time in purgatory. This is COMPLETELY unbiblical, so it’s not wonder that Martin Luther disagreed with it.
So your second answer is:
THE SALE OF INDULGENCES BY CHURCH OFFICIALS
Yeah….the Catholic Church was pretty messed up