Slight update. I just don’t feel that Luke’s “final lesson” line feels right when put into context, only because it doesn’t match his tone and cadence in the scene. I love the line itself, but it just doesn’t seem like it’ll work seamlessly.
What about something like this? If possible…
Luke Skywalker: Rey, some things are stronger than blood. Confronting fear is the destiny of a Jedi. Your destiny, and my final lesson. If you don’t face Palpatine, it will mean the end of the Jedi, and the war will be lost.