In Star Wars: The Empire Strikes Back, Luke goes to Dagobah to receive training from Yoda, a Jedi Master. As the training progresses, Luke sees his X-Wing sink deeper into the swamp where it landed. Yoda tells him to use the force to get it out of there. He tries, but manages to levitate it only slightly.
When he gives up and sits on the bank, he tells Yoda, “Master, moving stones around is one thing. This is totally different.” Yoda gives him some encouragement to which Luke tells him, “I’ll try.” Yoda tells him, “No! Try not. Do. Or do not. There is no try.”