Revelation is a Prowess, this special kind of Feat can't be acquired unless the character has Divine Touch. A Prowess is a special action that can only be done once per scenario. Like any Feat, it can be acquired only once.
You gain some insight into the future. This insight might come from a dream, the usage of drugs or some form of divination.
The Game Master can choose to give you some insights into the events to come or at least have to describe you in detail the next event on the Ambiance Track.