I looked up a relevant passage in the novel yesterday. When Tessio is arguing about Barzini's incursions, and wants to recruit more men, Vito replied: "I gave my word, and I can't break it," or something to that effect. Tess replies that Barzini's actions are "provocation enough," presumably to constitute "breaking the peace."
Ntra la porta tua lu sangu � sparsu, E nun me mporta si ce muoru accisu... E s'iddu muoru e vaju mparadisu Si nun ce truovo a ttia, mancu ce trasu.
