Star Wars: 10 Greatest Disturbances In The Force

While training Luke on the planet of Dagobah, Yoda uses his exceptional power to actually manipulate the Force into creating a disturbance he knew Luke would feel. Whether it was a lesson or a test, Yoda could only create the disturbance before letting Luke dictate its development. When Yoda tells Luke his weapons won't be needed, the apprentice shoots his master a doubtful look before putting on his blaster belt equipped with none other than his father's former lightsaber. 

As soon as Luke enters the cave, which is a common mythological motif pertaining to transition in the hero's journey, he is approached by Yoda's meditated manifestation of Vader. Fearful, Luke ultimately strikes the figure down, but then sees his own face under the mask once it's blown off.

The important take away from this disturbance is what Luke learns about the Force: you get what you give. Luke's enlightenment reveals the dark side is rooted within everyone regardless of intent and cannot be completely controlled; he must instead learn to be open and trust in it. 

This is the most important lesson Luke will use when confronted by the emperor as it eventually compels him to tacitly toss his lightsaber aside and solidify his sacrifice, which ultimately forces Vader to step up or stand by.