Fauchelevent's character allows the reader to gain further insight into Jean Valjean. When Fauchelevent is trapped beneath his cart, Valjean, undercover as Monsieur Madeleine, selflessly comes to his aid. After Valjean attempts to enlist the help of bystanders to lift the cart, Javert remarks that the only man he’s ever known capable of such strength is an old convict. Knowing that it may reveal his identity as the convict in Javert's story, he nonetheless ignores Javert's "vulture gaze" and lifts the cart, saving an innocent man's life. This choice highlights Valjean's unwavering commitment to virtue and compassion, even at personal cost. It also foreshadows his eventual decision to turn himself in to the authorities to spare Champmathieu's life.
The cart accident is a key moment for Fauchelevent as well, transforming him from a critic of Valjean into his unlikely savior. Prior to the incident, Fauchelevent is fueled by petty jealousy and envies Valjean's success after years of his own financial struggle. However, after Valjean saves his life, Fauchelevent changes his outlook. He comes to view Valjean as a saint, begins to take "pleasure in his sense of gratitude," and is eager to commit good deeds. In fact, when Valjean later comes across Fauchelevent and asks for assistance, Fauchelevent replies, "I thank God if I can repay something of what I owe you." Fauchelevent illustrates the way in which a simple act of kindness can have a ripple effect. This chain reaction starts when Bishop Myriel frees Valjean and gives him the candlesticks. In turn, Valjean commits to a life of honor and virtue, selflessly helping characters like Fantine, Cosette, Marius, and Fauchelevent. Similarly, after Valjean saves his life, Fauchelevent is deeply grateful, ultimately offering sanctuary to Valjean and Cosette. Valjean even takes Fauchelevent’s name as an alias. Thanks to Fauchelevent’s kindness, Valjean is able to escape his past and live in peace with Cosette for many years at the Convent.