Move over, Alfred Hitchcock. St. Gregory the Great was telling spine-tinglers 1300 years before you were born.
You’ll find much of his collection of ghost stories in his Dialogues, many of which were quoted by F. X. Schouppe, SJ, in his Purgatory. And it is to warn the reader of the punishments of purgatory, and to solicit masses to be said for the dead, that St. Gregory tells the stories.
But he begins with a further warning–don’t think you can live like you want now and hope to be purged then:
Yet we have here further to consider, that none can be there purged, no, not for the least sins that be, unless in his lifetime he deserved by virtuous works to find such favour in that place.
Gregory admits immediately that these are not stories of things that he has seen or heard. No, he’s just passing on stories that were told to him, from folks he trusted. These are sixth century Urban Legends, in other words.
After telling the first tale, a typical story of a ghost begging for penitential acts to be done on his behalf, Gregory’s interlocutor, Peter, asks,
What, I pray you, is the reason, that, in these latter days, so many things come to light, which in times past were not known: in such sort that by open revelations and manifest signs, the end of the world seemeth not to be far off?
In other words, “Why are we hearing of these new teachings, that come from the mouths of the dead?” And Gregory goes on to say that at the border between two eras there’s going to be a little spiritual bleed-through, as it were.
The stories go on, stressing the value of offering sacrifice on behalf of the dead. But nowhere does Gregory quote the passage from 2 Maccabees that is usually offered as the justification for this. Instead, he does it because the ghosts of the dead asked for it.
One of the stories is of a monk Justus. It seems he hid three coins from his fellow monks, and only told his brother where they were. But the monks had found them, and Gregory just couldn’t fathom how this faithful monk could have committed such a sin. So he decided to teach a lesson to one and all. None of the monks were to visit Justus in his final agony to comfort him–and his brother was to tell him why, so that hopefully he’d die with some remorse.
and when he is dead, let not his body be buried amongst the rest of the monks, but make a grave for him in some one dunghill or other, and there cast it in, together with the three crowns which he left behind him, crying out all with joint voice: ‘Thy money be with thee unto perdition’; and so put earth upon him.”
They then waited 30 days, after which Gregory offered a daily mass for Justus for 30 days. And after 30 days, the ghost of Justus appeared to his brother and said he was now at peace.
And that custom of offering a 30 day series of “Gregorian Masses” for the dead is still available (examples: here, here, here, and here), usually as a source of revenue for missionary orders, with prices ranging from $150 to $500. (By way of comparison, the dioceses of Texas have set mass stipends at $5 per mass, and the intention is not to be refused if someone cannot pay).