Luke probably should have mentioned that timelines didn't seem to matter in this place, but he hadn't had the opportunity to really troll someone since before Bespin, when being part of a squadron was like being part of the boys; flying for freedom and fighting the Empire. Getting a chance to grab that again... it wasn't very Jedi like, but where was the harm?

"Hey, don't act like that," he replied, feigning being wounded by his words. "Fifty is young in my galaxy; some people live to nine hundred!"

Granted, some of those people were whatever species Yoda had been, but he didn't need to know that.