The tone of The Bride of San Luis Rey is by turns sardonic and earnest. Even though Wilder uses an antiquated style to enhance the story's historical setting, the narrator frequently makes witty quips that represent a modern sensibility and skepticism of 18th-century social mores. For example, when describing the widespread mourning that accompanies the bridge collapse, the narrator says that:
Servant girls returned bracelets which they had stolen from their mistresses, and usurers harangued their wives angrily, in defense of usury.
Even though this passage is addressing something very serious, the bridge collapse, the narrator is also joking about the trivial ways through which people sometimes express deep grief: in this case, the servant girls repenting for petty crimes, or the "usurers" defending an activity about which they may feel secretly guilty. Likewise, the narrator pokes fun at the provincial culture in Lima and the intellectual paralysis caused by the ongoing Inquisition. The lightly mocking tone here reflects a modern sensibility and reminds the reader that the narrator is commenting on the novel's events with a 20th-century perspective.
Even while cracking jokes about culture and social norms in colonial Lima, the narrator is extremely serious about the moral questions with which each of the protagonists are grappling. Many of the novel's characters are outcasts, or social pariahs: Doña Maria is frequently drunk in public, while Uncle Pio is considered even more disreputable than her. However, the narrator treats them and the central problems of their lives with great dignity. The most affecting passages of the novel occur when characters are able to find some meaning in their worst experiences. In the novel's final moments, as the Abbess reflecting on the tragic loss of life during the bridge collapse, she experiences an epiphany about the enduring nature of love, saying that,"all those impulses of love return to the love that made them." In these moments, the narrator's serious tone emphasizes the profound conclusions at which the characters arrive through self-examination.
Likewise, in an intensely class-based colonial society, the narrator treats people from different walks of life as equally worthy of serious consideration. They devotes the same attention to the relationship between Esteban and Manuel, two orphaned day laborers, as he does to the predicaments of Doña Maria, a wealthy noblewoman. In doing so, the novel argues that despite difference in their education, circumstances, and the ways they express themselves, all people are equally equipped to confront thee moral dilemmas of their lives—a message that is relevant in any era.
Ultimately, the narrator's humorous and serious moments work together to emphasize the distance between Lima's deeply flawed social norms and Wilder's own values as a thinker and a writer, which are expressed in the sincere depiction of each character's inner life.
