You’ve got it. Acts of charity can merit an indulgence, but the claims that one could purchase one’s way out of Purgatory or Hell, or be forgiven of a sin without being sorry for ones failing was contrary to the teachings of the Catholic Church, and remains to.
While I’m on a roll, I’ll drop the dime on the Chained Bibles.
Many Anti-Catholic arguments in the past took the same tact as with the false allegations that the Church sold indulgences, by claiming that the Catholic Church had a concious effort to keep the Bible away from Catholics. One proof was that in many Catholic Churches the Bible was attached to the pulpit by a heavy chain. Well here is the real story.
Bibles up until the time of Luther where published one of two ways. Monks would copy the Bible, or any book for that matter by hand, letter by letter. The second way was to cut a board with the entire page you wanted to print by hand. That means you would have to decide what you wanted on a page, and then with hand tools cut all the words onto the board backwards. If you made an error, you would have to start over again. So any book, most of all a Bible or large Missal took much time to copy. Paper was not used, but the hides of sheep or cattle, (that is why a diploma is called a sheep-skin, all important documents where written on animal skins, called vellum) Just like Tetzel and others who faked relics have always been around, there have been people who have stolen things of value from churches, to sell. Bibles where chained to Pulpits not to keep them from people, but to keep them from being stolen.
Another false accusation about the Catholic Church is that the Church kept the Bible in Latin so the people could not read it. The fact is long before Luther, the Bible had been translated not only into the languages of the people, (in Germany there where some 34 or so German translations of the Bible approved by the Catholic Church) but there where also bibles that where picture Bibles for those who could not read. If you visit Europe and go into the grand cathedrals the stories from the Bible are carved into the stone and depicted in the stained glass windows. Most of these cathedrals pre-date Luther and the founders of other Protestant Churches.
Without the Catholic Church, and Monks who copied the Bible by hand, we would probably not have the Bible today. The ancient texts we have in museums today are fragments. If the Catholic Church was the all powerful evil entity that many anti-Catholics claim it to be, Tetzel would have been covered up, and the Bible would have been hidden rather than hand copied and used in the Mass and Liturgy of the Hours, and other Catholic Rites in every Catholic Church every day.