As it is typical in good vs. evil combats, the forces of good are initially shown powerless, with no one to help them and with no thought on how to remedy the situation they find themselves in. The Pevensies themselves are unable to reach Caspian and the rest of the Narnians because they constantly come across impediments. The overall purpose of the heroes in this book is to return purity in a ruined land, this being a reference to how the forces of good ultimately have to defeat the forces of evil and impose their influence over the land, so as for it to become pure once more. As customary for a land conquered by evil, many of those previously devoted to good have lost their faith and are inclined to believe that there is no hope for them. The story can be considered to be a parallel to modern-day society, given that Lewis recognized how more and more Christians turn away from their faith, given that their life experiences...

In spite of the fact that the forces of good use violence to accomplish their goal, they do so when they have no other alternative and eventually put across their honorable nature.
Lewis' inspiration for "Prince Caspian: The Return to Narnia" was most probably a combination of stories from the Bible, given that one can identify more than one events that resemble biblical accounts. With episodes involving individuals viciously turning against their own family and expressing their desire to achieve as much material wealth as possible regardless of the expenses, it becomes obvious that this book is meant to show evil in one of its most authentic forms. The efforts that the forces of good go through, their lesser number, and the fact that they initially have little chances against their oppressors demonstrate how good is always threatened, but that it can emerge victorious if people have faith.