I did a search for threads about ghosts on this forum and I had a look at a couple of them.
What I want to know is, is it possible for the soul of a departed person to manifest itself after death to people on earth to ask for prayers? Such a possibility seems to be affirmed by Roman Catholics that souls in Purgatory can manifest themselves to ask for prayers. There is a "Purgatory Museum" in Rome which contains artefacts that have burnt hand prints imprinted on them as "proof" that a soul in Purgatory has visited. I remember reading about Borley Rectory, a haunted house in England, and mysterious writing appeared on a wall. One of the things written is "Marianne (the rector's wife) light mass prayers". This seems to fit with a departed soul requesting prayers.
I know that Orthodox Christians don't believe in the Roman Catholic teaching of Purgatory, but you do pray for the dead. So, according to Orthodox teaching, is it possible for departed souls to appear to the living to request prayers, or to make their presence known by moving things, etc?
I know that some paranormal activity is definitely caused by demons, but saying that it is all demonic does not explain why a ghost disappears after his/her bones are found and given a proper burial.
There are many reports of Orthodox Saints showing up and interacting with people or ministering to them, Saint John Maximovitch and Saint Nectarios come to mind and also Fr. Seraphims Rose.