Star Wars is a mythic adventure, but why has the lightsaber of Anakin Skywalker become so central to its mythology? The first Star Wars movie saw an unsuspecting Luke Skywalker stumble into a whole galaxy's worth of adventures when he made his way to Obi-Wan Kenobi. There, Luke learned his father had been a Jedi, and he was given his father's lightsaber.
That lightsaber served Luke well until The Empire Strikes Back, when he confronted Darth Vader on Bespin. This was the lowest moment of Luke's life; he was defeated by Darth Vader, disarmed, and then told the horrific truth - that Vader was his father. Tie-in comics have revealed that Luke returned to Bespin in an attempt to find the lightsaber, but he was unsuccessful, and it found its way into other hands.
The lightsaber resurfaced in Star Wars: The Force Awakens, having somehow been acquired by Maz Kanata. Rey sensed the blade calling out to her, and when she touched it she experienced a "Forceback," a Force-induced vision of the past. Although Rey initially resisted the lightsaber's call, she was forced to accept it, and by Star Wars: The Last Jedi she was willing to fight to keep it. When the sequel trilogy came to an end, Rey buried Luke's lightsaber alongside Leia's in the desert sands of Tatooine. The scene was evocative of Excalibur being returned to the Lady of the Lake, symbolizing that it could return in the future when and if needed. But what is so special about this lightsaber?
A Jedi Bonds With Their Lightsaber
The mechanical construction of a lightsaber is relatively straightforward, but its power comes from a rare kyber crystal. These are living crystals, perfectly attuned to the Force, and in the tie-in novel Catalyst scientist Galen Erso noted their lattices appear to shift, as though exhibiting some sort of emotional spectrum. In order to create a stable lightsaber, a Jedi needs to bond with the kyber, which has been described as "a lens that focuses the light inside the Jedi." Thus a Jedi's lightsaber is no mere weapon, but rather is bonded to them through the Force.
That has profound implications for Anakin Skywalker's lightsaber. It was created by the Chosen One himself, a being of unprecedented power who was destined to bring balance to the Force. What's more, Anakin used the lightsaber for years, throughout the Clone Wars. According to the recently-published Secrets of the Jedi, that would have enhanced the bond between Anakin and his lightsaber:
"It's said that wielding a lightsaber is less like swinging a sword and more like directing a current of power. When you're attuned to the Force, your thoughts and actions all become part of the same flow of energy, which is then directed through the kyber crystal and into your lightsaber's blade."
When Obi-Wan Kenobi retrieved Anakin Skywalker's lightsaber after defeating him on Mustafar, he was not simply picking up a memento to remind himself of his failures. Rather, he was saving a unique blade, one that was unusually strong in the Force - and carried a part of Anakin Skywalker within it. Although Luke used the lightsaber a lot less than Anakin, he too would inevitably have bonded with it before losing the blade in The Empire Strikes Back. This explains why Rey could hear the lightsaber "calling" to her in Star Wars: The Force Awakens; she was destined to join herself to the same Skywalker legacy, and thus she was sensing echoes of Anakin and Luke beckoning her to them.
Rey's Bond With The Lightsaber Is Even More Profound
The lightsaber was badly damaged in Star Wars: The Last Jedi, and even the kyber was cracked. According to Rae Carson's novelization of Star Wars: The Rise of Skywalker, Rey then spent months poring over ancient Jedi texts in order to learn how to repair it. This was how she discovered a unique new version of Force Heal, which she first used to restore the kyber. Rey's Force Heal power is subtly different to anything seen before in Star Wars lore, because it involves the transfer of life energy from one being to another. Thus, Rey bonded with the kyber in a unique way, pouring her own life energy into it.
Rey took the repaired lightsaber with her to Exegol, and used it when she faced the resurrected Emperor. She used it to absorb Palpatine's lightning - an act that takes on a new degree of significance when you understand what was happening in that scene. Secrets of the Jedi suggests a lightsaber absorbs Force Lightning into its own current, an energy field that embodies the Skywalker legacy. Therefore in a very real sense, the Emperor is being opposed by the Skywalkers united - Anakin, Luke, and Rey. When Rey added Leia's lightsaber into the mix, she was bringing a poetic conclusion to the saga, because all the main heroes are united against the Sith Lord in that moment.
Anakin Skywalker's Lightsaber Has Become Star Wars' Excalibur
After the Battle of Exegol, Rey replaced Anakin's lightsaber with one of her own design. This was constructed in part from Rey's staff, which - according to Jason Fry's novelization of Star Wars: The Last Jedi - she already seemed to have something of a Force-bond with. She then chose to bury Luke and Leia's lightsabers on Tatooine, in a scene designed to honor the legendary blades.
Star Wars has always been heavily influenced by legends and mythology, and in this case JJ Abrams was drawing upon Arthurian myth. The scene was deliberately reminiscent of the moment Excalibur was returned to the Lady of the Lake, symbolizing both the end of the age of Camelot and the possibility the One True King would return in England's hour of greatest need. In exactly the same way, Rey's burial of the lightsabers represents the dramatic conclusion of the Skywalker saga, now Palpatine has been defeated at last; but though the age of the Skywalkers has finally come to an end, they will always be there should they be needed. It's not hard to imagine a time millennia in the future where the Force guides a desperate Jedi to Tatooine, and they find themselves wielding two legendary blades; bonded with the same weapons that were used by heroes of the past. A fitting end for the main Star Wars story.