The Passion allows its user to accurately foresee the detailed futures of any of their blood related relatives, allowing the user to make their own prophecies. It can predict actions from a few seconds later to events in the extremely far future.
The ability is not limited to only their immediate relatives. It allows them to foresee the future lives of even the incarnations of their relatives in subsequent universes. Dio is capable of using the ability on both his own and Jonathan's relatives.
Dio uses the ability while underwater in his coffin for one hundred years, devising a plan that will let him become the ultimate life form. He also uses it on Giorno Giovanna who is from an unknown universe, admitting he didn't pay much attention to Giorno in future universes after foreseeing the original Giorno defeat Diavolo in the first universe.