YODA: Why wish you become a Jedi? LUKE: Mostly because of my father, I guess. YODA: Ah, your father. Powerful Jedi was he.
Now that's some tasty dramatic irony. At this point, all Luke knows about his dad is what Obi-Wan told him—that he was a great warrior and an exceptional pilot. Kid's got a big surprise in store.
YODA: Much anger in him, like his father.
Seriously, guys—there's going to be a lot of dramatic irony in the section. This quote alludes not only to the revelation of Luke's parentage, but also to his own struggles with anger.
[Luke decapitates a manifestation of Darth Vader in a mystical cave on Dagobah. The head explodes to reveal Luke's own face beneath the helmet.]
Although you could easily interpret this scene metaphorically—as a representation of Luke's struggle with anger—it raises a few questions. Does Luke already realize, on some level, that Vader is his dad? That would certainly explain why he accepts the claim so readily. What do you think?
OBI-WAN: That boy is our last hope. YODA: No. There is another.
While there's a lot of debate over the nature of this line, the most common interpretation is that it references Leia, who Luke doesn't yet realize is his sister. The Skywalker family tree is so messed up that it looks like a Rancor attacked it.
VADER: Your destiny lies with me, Skywalker. Obi-Wan knew this to be true.
You know, Vader could just be trash-talking here, but he might have a point. After all, why would Obi-Wan lie about the fate of Anakin Skywalker if he wasn't worried about Luke heading down the same path?
VADER: Obi-Wan never told you what happened to your father. LUKE: He told me enough. It was you who killed him. VADER: No. I am your father.
Here it is, folks: the paternity test heard around the world. The idea that Luke—who represents goodness and innocence—and Vader—who represents pure evil—are father and son transforms our understanding of not just this film, but also of A New Hope.
VADER: Join me, and together we can rule the galaxy as father and son. Come with me. It is the only way.
This makes us feel like Darth Vader cares about Luke more than he wants to admit. In this interpretation, Vader isn't trying to turn Luke to the dark side to protect the Emperor or defeat the Rebels—he's doing it so he can reunite with his son.
LEIA: Luke...We've got to go back. LANDO: What? LEIA: I know where Luke is.
For context, Luke has just telepathically contacted Leia so she can rescue him. This is the film's second subtle hint that these two almost-lovers are siblings, which is explored further in Return of the Jedi.
[Luke and Vader are on different ships communicating telepathically.] VADER: Luke. LUKE: Father. VADER: Son, come with me.
What you can't hear in these transcribed lines is Luke's tone of voice: He sounds eager, almost longing. He feels conflicting emotions towards Vader/Anakin because his entire self-image has been built around a false (or, at least, incomplete) image of his father.
LUKE: Ben, why didn't you tell me?
Obi-Wan was a father figure for Luke, so it breaks the kid's heart to know that he was lied to. You know, if we didn't know any better (or hadn't seen Return of the Jedi), we might think that this was the perfect setup for a dark side turn...