SPOILERS for Star Wars: The Last Jedi ahead
Star Wars: The Force Awakens, fans new and old flocked to theaters to find out what Luke Skywalker, Leia Organa, and Han Solo had been up to since viewers last saw them. Though fans got to catch up with Leia and Han, Luke remained a mystery and didn’t appear until the very end of the film.
However, it was said in The Force Awakens that he had been in search of the first Jedi temple and when newcomer Rey finds Luke on Ahch-to in The Last Jedi, we know he found it. Throughout the course of The Last Jedi, Rey attempts to convince Luke to teach her in the ways of the Force, and he finally relents, showing her the temple and the ancient Jedi texts. But, the ongoing war between the Resistance and the First Order draws Rey away from Ahch-to and back into the fight. Once gone, Luke contemplates his own future and relationship to the Force.
Related: What Does The Last Jedi Reveal About Rey’s Parents?
In perhaps one of the more shocking moments of Yoda, appears to him as a Force ghost. When Luke wavers and is unable to set fire to the tree knowing that the texts are inside, Yoda commands a bolt of lightning that instead does the job. In his final words to Luke, as the two watch the tree burn, Yoda says:
“Wisdom they held, but that library contained nothing that the girl Rey does not already possess.”
Later on, in a blink-and-you’ll-miss-it moment when Finn is pulling a blanket out of a drawer, the Jedi books are visible to the viewer. It’s with this shot that the true meaning of Yoda’s words are revealed. Rather than saying Rey metaphorically possesses all the knowledge of the Jedi library, indicating - as the viewer and Luke may presume - there’s nothing those books could teach her, Yoda meant she literally possessed the books. Presumably, Rey stole the Jedi texts before she left Ahch-to on the Millennium Falcon.
Now, it remains to be seen if the Jedi books will play a big part of Rey’s further training to master the Force in or before Kylo Ren - and that doesn’t seem a viable option if she’s to remain on the Light side of the Force - those books are her main resource for learning about the Force. That doesn’t necessarily mean Star Wars fans will get to learn more about what those texts actually say, though, since it’s unclear whether Episode IX will pick up immediately after The Last Jedi or feature a time jump.
That said, The Last Jedi makes a point of letting the viewer know Rey stole them from the library on Ahch-to, which would seemingly indicate they’ll be important to Episode IX in some way. Certainly, the reveal at the end of the movie of the books being on the Millennium Falcon also works as payoff to Yoda’s prank on Luke, but it’s likely they’ll also play a major part in Rey’s Force training. Plus, with the death of Luke, who was thought to be the last Jedi, it’s now up to Rey to keep the Jedi Order alive - and those texts will go a long way in teaching her about the Order’s history.