Luiza does not notice that Bazilio hasn't replied to her letters for months, and when the postman delivers the letter at her home, it grabs Jorge's attention due to it being addressed to Luiza and being sent from France. He reads the letter and discovers the adultery of his wife. The evidence of her betrayal makes him go into despair but nevertheless, he forgives her because of the strong love he feels for Luiza and due to her fragile health.
Luiza is oblivious to Bazilio's months-long silence, but when a letter arrives addressed to her from France, Jorge notices it. He reads the letter and discovers his wife's infidelity. This revelation causes him immense despair, yet he forgives her due to his deep love for Luiza and her fragile health.