This article goes to the speeches of Hecuba and Polymestor, in Hecuba, by Euripides. The objective is to show the different roles that the metaphor, theorized by Aristotle in both Rhetoric and Poetics, plays in them. Taught by these indications, it is confirmed that the requirements established in the aesthetic text are directed to emphasize persuasion (purpose of rhetoric) major of the contenders objective to justify their actions.