Capellio and Tebaldo address their followers advising rejection of an offer of peace to be brought by an envoy from Romeo, the man who had killed Capellio's son. Tebaldo states that he will avenge the killing to celebrate his marriage to Giulietta: (Cavatina: "È serbata a questo acciaro" / "And reserved for this sword / is the vengeance of your blood") and he urges Capellio to hasten the moment when he may marry Giulietta and then avenge Capellio. The doctor, Lorenzo, objects that Giulietta is ill with a fever, but Capellio brushes his warning aside and declares the wedding will take place immediately. Tebaldo proclaims his love for Giulietta: "Sì: M'Abbraccia" / "I love her so much / She is so dear to me". Capellio's men urge him on and arrangements are made to have the wedding take place that day.