Star Wars: Episode IV – A New Hope

Darth Vader: "Your powers are weak, old man."
Obi-Wan Kenobi: "You can't win, Darth. If you strike me down, I shall become more powerful than you could possibly imagine."

Darth Vader: "I've been waiting for you, Obi-Wan. We meet again, at last. The circle is now complete. When I left you, I was but the learner, now I am the master."
Obi-Wan Kenobi: "Only a master of evil, Darth."

Obi-Wan Kenobi: "I have something here for you. Your father wanted you to have this when you were old enough, but your uncle wouldn't allow it. He feared you might follow old Obi-Wan on some damn fool idealistic crusade like your father did."
Luke Skywalker: "What is it?"
Obi-Wan Kenobi: "Your father's light saber. This is the weapon of a Jedi Knight. Not as clumsy or random as a blaster, an elegant weapon for a more civilized age. For over a thousand generations, the Jedi Knights were the guardians of peace and justice in the Old Republic. Before the dark times... before the Empire."

Luke Skywalker: "How did my father die?"
Obi-Wan Kenobi: "A young Jedi named Darth Vader, who was a pupil of mine until he turned to evil, helped the Empire hunt down and destroy the Jedi knights. He betrayed and murdered your father. Now the Jedi are all but extinct. Vader was seduced by the dark side of the Force."

"I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened."

"In my experience, there's no such thing as luck."

"Your eyes can deceive you, don't trust them."

"The Force is strong with this one."
[talking about Luke]