As a child, Chirrut was chosen as a padawan and taken to the Jedi Academy where he lived and trained until his late teens/twenties and began taking more off-world missions.

Being particularly religious it's only natural he makes a pilgrimage to the Holy City of Jedha.

Where he meets Baze, a friendless young monk.

(Baze learns to trust, Chirrut choses love. Maybe there's so angst in between?)