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 unaware of Bazilio's silence, which leads Jorge to discover his wife's infidelity through a letter from France. The evidence of this betrayal drives him into despair but he chooses forgiveness because of his strong love for Luiza and her weakened state.