Noble Warriors Trilogy #1: Seeker book by William Nicholson

This first novel in the Noble Warriors sequence begins when sixteen-year-old Seeker's older brother is publicly humiliated and--with no explanation--exiled from the Nomana, a revered order of warrior monks. Seeker refuses to believe that his beloved older brother is capable of committing a betryal that would warrant such severe consequences, so he sets off alone on a journey to rescue his brother and find out at last what really happened.

Along the way he meets two other young people who are on quests of their own, and in a shocking turn of events, the three are soon caught up in a harrowing and bloody race to save the Nomana--and themselves--from destruction.

An epic coming-of-age story about courage, friendship, desire, and faith, Seeker marks the beginning of a riveting new series.