The Guardian's Mantra was a prayer spoken by members of the Guardians of the Whills, who protected the Temple of the Kyber in Jedha City on Jedha. The Mantra, written by an unknown author, was found in Collected Poems, Prayers, and Meditations on the Force, edited by a Disciple of the Whills named Kozem Pel. The Mantra was spoken during times when spiritual guidance from the Force was needed.
Following the execution of Order 66 in 19 BBY, former Jedi Padawan Ahsoka Tano, on the run from mind-controlled clone troopers aboard the Venator-class Star Destroyer Tribunal while it was in hyperspace, recited part of the Guardian's Mantra while using the Force to search for the control chip inside the head of her friend Clone Commander Rex so it could be removed. Despite being unconscious, Rex began to recite along with Tano as she was doing this.
Guardians of the Whills Chirrut Îmwe and Baze Malbus, who were killed while helping to steal the plans to the Death Star during the Battle of Scarif, both spoke the Mantra in their final moments.
The Guardian's Mantra first appeared in the 2016 movie Rogue One: A Star Wars Story. It was first identified by name in the junior novel Guardians of the Whills.