“Destiny” is episode fifteen of season three of Star Trek: Deep Space Nine.
With a peace treaty now in place between Cardassia and Bajor, thanks to Vedek Bareil in “Life Support”, two Cardassian scientists are coming to the station to try and set up a communications relay through the wormhole to allow communication with ships in the Gamma Quadrant.
Vedek Yarka (played by Erick Avari, Stargate SG-1‘s Kasuf) asks to meet with Sisko because he says that this visit matches a Bajoran prophecy, one which appears to state the wormhole will be destroyed. However, the prophecy seems to say three Cardassians will visit the station, and there are only two. Then a third arrives.
The Vedek turns out to have actually been stripped of his religious rank, but more and more elements of the prophecy appear to be coming true, which affects Major Kira. She has to deal with her religious beliefs – ones which state that Commander Sisko is the Emissary of the Prophets – within the bounds of her regular job, in which he is just her commanding officer.