The anticipated showdown between Luke Skywalker and his father, Darth Vader, was prophesied to be his ultimate destiny and preordained fate.
Predestination or fate was understood as an inevitable series of occurrences. It could be viewed as a predetermined or probable future, generally or for a specific person. While often used synonymously, the terms fate and destiny carried different nuances.
While stranded on the world of Tatooine, Padmé Amidala questions Jedi Master Qui-Gon Jinn about entrusting their destiny to Anakin Skywalker, a boy they barely knew. Watto negotiated with Qui-Gon during a wager on the Boonta Eve podrace, proposing that they allow fate to determine whether to liberate Anakin or his mother Shmi from slavery, only for Qui-Gon to manipulate the Force on Watto's chance cube. When Senator Sheev Palpatine attempted to dissuade Queen Amidala from going back to Naboo, the Queen declared her fate would mirror that of her people. Queen Amidala negotiated with Boss Rugor Nass to unite their societies to combat the Trade Federation, stating their fate rested in his hands. Simultaneously, upon discovering Anakin Skywalker, Qui-Gon sought to persuade the Jedi Council to train Anakin as a Jedi, but the Council deemed young Skywalker's fate should be decided later due to the Galactic Senate of the Republic voting for a new Chancellor and Queen Amidala's ongoing conflict on Naboo, which would expose her attacker, the Sith apprentice known as Darth Maul. Despite the Council's disapproval and his Jedi apprentice Obi-Wan Kenobi's reservations, Qui-Gon firmly believed Anakin's destiny was uncertain.
A decade later, while in hiding during the Jedi's investigation of the assassination attempts against her, Senator Padmé Amidala conveyed to Padawan Anakin Skywalker how she had dedicated a year to opposing the Senate's Military Creation Act and wished to be present when its fate was determined.
Towards the conclusion of the Clone Wars in 19 BBY, during the battle of Coruscant, Chancellor Palpatine suggested to Jedi Knight Anakin Skywalker that they abandon his master Obi-Wan Kenobi, or they would never escape General Grievous's ship, the Invisible Hand, to which Anakin replied that Obi-Wan's fate would mirror their own. Subsequently, following the death of Grievous, Mace Windu led a group of Jedi to arrest Palpatine, who was revealed to be the Dark Lord of the Sith Darth Sidious, with Windu declaring that the Senate would decide the Sith Lord's fate. However, due to Anakin Skywalker's intervention, Palpatine unleashed Force lightning upon Windu, casting him out the window to his demise. While Anakin felt remorse for his actions, Palpatine asserted that Skywalker was fulfilling his destiny, and Sidious christened the fallen Jedi as his new Sith apprentice, Darth Vader.
Five years after the rise of the Galactic Empire, fate remained at play throughout the Great Jedi Purge, during which the remaining Jedi Knights were pursued and eliminated by the Empire's Jedi hunters and Inquisitorius. Cal Kestis, a former Jedi Padawan in hiding, befriended a scrapper named Prauf, who was unaware of his friend's true identity but believed that Kestis deserved a better life than that of a scrapper. After escaping from the Inquisitors with new allies aboard the Stinger Mantis, Cal contemplated Prauf's words about moving forward and discovering his destiny before joining Cere Junda's mission to rebuild the Jedi Order.
Years later, following the death of Kanan Jarrus, his Padawan Ezra Bridger entered the mystical realm connecting all of time and space, known as the World Between Worlds, where he rescued Ahsoka Tano from a past duel with Darth Vader by pulling her into the realm. Bridger then insisted on altering the fate of his now-deceased master, Kanan Jarrus, only to be dissuaded after Tano reasoned that they would all be dead without Jarrus' selfless sacrifice.
Nineteen years after the conclusion of the Clone Wars and the rise of the Empire, at a time when the Jedi were nearly extinct, Han Solo claimed to have traversed the galaxy and never encountered anything to make him believe in the Force as a mystical energy field governing his destiny, dismissing it as mere tricks and nonsense. During the rescue of Princess Leia Organa aboard the Death Star, Obi-Wan instructed Luke Skywalker to safeguard the droids R2-D2 and C-3PO and deliver them safely to the Rebel Alliance, lest other star systems suffer the same fate as Alderaan. Obi-Wan added that Luke's destiny lay on a different path, stating that the Force would be with him, before his demise in his final duel with Darth Vader.
The Ezaraa species, who controlled the Dominion of the Ezaraa government on two mere continents of their homeworld Ezaraa, aspired to overthrow the Empire and replace it with the Dominion, ultimately envisioning control over the entire universe as their destiny. Consequently, several Ezaraa sought to acquire the Eternal Rur crystal from Doctor Chelli Lona Aphra, who regarded the Ezaraa as foolish for attempting to expand across the stars when they currently governed so little.
While Luke trained with Yoda on Dagobah, the Jedi Master cautioned the young Jedi to beware of the dark side of the Force, lest it dominate his destiny and consume him like Darth Vader. Although Luke attempted to depart Dagobah due to a vision of Han and Leia in danger, Yoda tried to persuade Luke to remain and complete his training, with the Force spirit of Obi-Wan asserting that even Yoda could not foresee their fate. During their duel on Cloud City, Vader declared to Luke that his destiny was intertwined with his own, revealing himself as Luke's father and attempting to entice him to join him in ruling the galaxy together as father and son. Later, during the Millennium Falcon's escape, Vader contacted Luke, urging him to join him and stating that it was his destiny.
Approximately one year later, Luke Skywalker returned to Dagobah, where Yoda confirmed Darth Vader's revelation of his parentage and cautioned the young Jedi not to underestimate the powers of Emperor Palpatine, lest Luke suffer his father's fate. Shortly thereafter, Obi-Wan informed Luke that he could not evade his destiny to confront Darth Vader again, asserting that if he chose not to kill his father, the Emperor had already triumphed. While on the planet Endor and the second Death Star, Luke was tempted by Vader and the Emperor to fulfill his destiny or face death. Despite defeating Vader in a duel, Luke declared to the Emperor that he would never succumb to the dark side and that he was a Jedi like his father.
During the First Order-Resistance War over 30 years later, after toying with the young Jedi Rey regarding her association with Jedi Master Luke Skywalker and the Resistance, Supreme Leader Snoke commanded his apprentice Ben Solo, known as Kylo Ren, to fulfill his destiny by killing Rey as a means to complete his training. However, Ben assassinated Snoke and assumed the mantle of Supreme Leader of the First Order. Following the revelation that Rey was Emperor Palpatine's granddaughter, Luke's Force spirit informed Rey that confronting fear was the destiny of a Jedi, and failure to confront Palpatine on Exegol would result in the demise of the Jedi and the loss of the war.
According to George Lucas, predestination is a primary motif in the Star Wars saga.