No no ... Obviously, the line:
"No. I Am Your Father" is the most powerful line through out all of the Star Wars films.
Yoda: "Size matters not. Look at me. Judge me by my size, do you? Hmm? Hmm. And well you should not. For my ally is the Force, and a powerful ally it is. Life creates it, makes it grow. Its energy surrounds us and binds us. Luminous beings are we, not this crude matter. You must feel the Force around you; here, between you, me, the tree, the rock, everywhere, yes. Even between the land and the ship. Luminous beings are we, not this crude matter."
Luke: "All Right. I'll give it a try."
Yoda: "No! Try not. Do. Or do not. There is no try."
Luke: I dont ... I don't believe it"
Yoda: "That is why you fail."
I don't know, there are so many.