As if picking up on his curiosity, Luke whipped out his communicator, navigating through the notes app to find where he tapped out the Jedi Code and handing it off to Marr. It's clear Luke's been giving his questions about the Force a lot of thought, as the note file is pretty huge, with notes branching off of notes off of other notes. It was very likely those notes were going to get even longer after their current conversation, but at the moment, the code in question was the highlight:

Emotion, yet peace.
Ignorance, yet knowledge.
Passion, yet serenity.
Chaos, yet harmony.
Death, yet the Force.

"'Learn to apply your own restraint'..." Luke echoed, thinking back, trying to remember when he had ever seen Vader apply restraint. His right hand clenched reflexively in response, and he gave up; if that was supposed to be restraint, then he didn't want to see what his father was like unrestrained. "I think that message was lost."