What hope is given to the people in his tomb saying Arthur is the one king and king that will be?

The hope given to the people in Arthur's tomb lies in the belief that he is not only a legendary king of the past but also a symbol of a future savior. This notion suggests that Arthur's return will herald a time of unity, justice, and strength for the realm. His enduring legacy inspires faith that when the nation faces its greatest challenges, he will rise again to lead and protect his people. Thus, Arthur represents both a historical ideal and an enduring promise of better days to come.