marcuz said:Does Obi-wan not want luke to kill his father? Luke says something like he cant kill him. I think at that point the prohecy was the furtherest thing from their minds
Luke doesn't want to kill him, but Obi-Wan says, "You cannot escape your destiny. You must face Darth Vader again"
Luke refuses to fight, but explodes in a rage when Vader suggest that Leia might be the one to turn to the ark side if Luke doesn't.
The end result is that Anakin's love for his son, causes him to turn back from the dark side, and destroy the Emperor, fulfilling the prophecy. Luke was never going to be the one who destroyed the Sith. It was always going to be Anakin, but without Luke, Anakin wouldn't have turned on the Emperor.
It's all one big circle!