As a novel about the effects of war, The Silver Sword confronts the effects of violence on a large scale and depicts a great deal of suffering. Although Serraillier never minimizes the hardship the family endures, he never graphically depicts the worst violence of the war.

The novel shows that goodness and courage continue to exist in individuals, despite the evils of war. Jan is a special example of this theme; he is an attractive and sympathetic character, particularly in his special touch with animals, but his various misdeeds often create added difficulties for the other children. His good intentions and genuine repentance make him forgivable even when he breaks the law. The final promise of a new society with peaceful ideals brings the book to a hopeful conclusion.