Vader: “If you only knew the power of the dark side! Obi-Wan never told you what happened to your father.”
I get so wrapped up in how iconic each line is individually that sometimes I forget to think of how they inform each other. The latter is obviously Vader leading up to revealing that he’s Luke father, and it’s proceeded by him boasting how powerful the dark side is. The overall point he was trying to make is that the dark side is so powerful even he, a great Jedi Knight that Luke looked up to, fell for it. Implying that Anakin became Vader because he was power-hungry and loved the dark side’s power.
The OT implied a much more Walter White-esque turn then the one we ended up getting.