There is little question that the Catholic Church believes in the reality of the spiritual realm — St. Paul in Ephesians speaks of “our wrestling is not against flesh and blood; but against principalities and power, against the rulers of the world of this darkness, against the spirits of wickedness in the high places.” But it is a realm inhabited by angels, demons, and of course, Satan himself. (And, if you’re an enlightened “post-Vatican II” Catholic like Fr. Richard McBrien, you can scoff at the very mention of the latter).
As far as ghosts are concerned, the prevailing tendency among Catholics is to look askance at the concept of “lost souls”, trapped in this life and waiting to cross over. There is scarce mention of “ghosts” in the Catechism and judging by the absence of clear, definitive teaching — the Church has refrained from adopting a firm position on their existence.
According to Gary Jansen, a contemporary Catholic from Rockville Centre, Long Island, ghosts simply didn’t exist. For him, “heaven, hell, angels were basic tenents of my Catholic faith, but never basic tenents of my life. . . . these topics were never discused during my twelve years of attending parochial school.” While his devout Catholic mother would mention strange occurrences, he prided himself on his rationality.
Until, that is, when he had an unsettling encounter in his son’s bedroom in 2007. Holy Ghosts: Or How a (Not-So) Good Catholic Boy Became a Believer in Things That Go Bump in the Night is an account of one Catholic’s real-life haunting: