Reported Private Revelations

In a reported private revelation, jesus shows sister mary dionysia a soul of a prince that's currently in purgatory. He foresaw her future prayers for him and gave him the grace he needed at the moment of death based on those future prayers. i don't know that these reported private revelations have ever been investigated and approved. They could be pious legends, accurate or otherwise inaccurate. But even if they are, they would still show that the idea of praying across time is not something new in christian thought. It has a history. And that history would stretch back to the 12 hundreds, if the report about saint gertrude the great is accurate.