Not long ago I completed several years of work on the birth of Purgatory. From the early days of Christianity Christians have shown by their prayers for the dead that they believed in the possibility of remission of sins after death. But the time, place, and manner of purgation for a long time remained quite vague, despite the suggested solutions to the problem put forward by Clement of Alexandria and Origen in the East, where Purgatory never took hold, and by Augustine and Gregory the Great in the West, where the location of Purgatory was never really defined before the twelfth century, in the final three decades of which the noun purgatorium first emerged. This veritable "birth" of Purgatory can be seen as part of a major shift in attitudes and feelings that took place around the turn of the thirteenth century, resulting in a new geography of the other world and in a new relation between the society of the living and that of the dead.I offer several comments:
It should be clear that Purgatory was not an Apostolic tradition. It was something that developed over time, and developed primarily in the West. There were some early Christians who prayed for the dead, hoping that their sins would be remitted, but keep in mind that some of these were hoping that people would be released from hell.
It is understandable that Christians "believed in the possibility of" or more precisely "hoped for" remission of sins after dead. After all, we ourselves would wish to have such a chance, should we find ourselves in a similar position. Nevertheless, such a belief or hope should not serve as a basis for our doctrine, however. Instead, we should cling to divine revelation.
Purgatory is like many other doctrinal innovations. It can be traced back to a number of lesser precursor errors. Nevertheless, in the final analysis, it plainly is an innovation. The reason there was no vocabulary word purgatorium before the second half of the 12th century was because there was no concept of such a place that needed that name. It's not that the place used to be called something else, it's that - as Le Goff says, there was "a major shift in attitudes and feelings that took place" and consequently there was born "a new geography of the other world and in a new relation between the society of the living and that of the dead."
We ought to reject these innovations, because they are not authentic Christianity: authentic Christianity is based on divine revelation. These doctrines of Purgatory are not apostolic tradition, nor do they become apostolic tradition, simply because some people had hope for posthumous remission of sins before the innovation of these peculiar doctrines.