Irony is defined as the narrator's choice to use language to juxtapose what is said to what it is intended to be said. This form of figurative language can manifest in epigrams, paradoxes, and sarcasm.
In "La Viuda de Montiel" the irony begins at the very beginning of the story, when Márquez describes the body of José (Chepe) Montiel at the day of his funeral. According to the narrator, the entire town feels avenged at the death of this man who, as the reader will later find out, was a despot. However, the manner in which the man's body is laid for eternal rest instills a feeling of veneration rather than hatred, particularly in the way that the body was prepared to lay to rest.
Estaba muy bien afeitado, vestido de blanco y con botas de charol, y tenía tan buen semblante que nunca pareció tan vivo como entonces. Era el mismo don Chepe Montiel de los domingos, oyendo misa de ocho, sólo que en lugar de la fusta tenía un crucifijo entre las manos.
Márquez uses antithesis to juxtapose the fact that this man's notorious, famous, and controversial life ended up like any "everyday Joe" would have ended. In fact, the simplistic and reductionist use of language denotes a tendency to downplay the man's life altogether, reminding us that, in the eyes of God, we are ultimately all the same: weak, sinful, and feeble.
José Montiel murió en su hamaca, un miércoles a las dos de la tarde, a consecuencia de la rabieta que el médico le había prohibido.
Another example of irony comes in the way that Montiel's surviving daughters, who live in Paris, describe the city to their mother. Far from the Parisian sophistication expected by the reader, we get a raucus, vulgar, and somewhat amusing account of Paris, namely, of how the pigs hang from the butchers' stands. The daughter places importance on the fact that a huge carnation is stuck in the anal cavity of the pig as an act of aestheticism.
"Imagínate, que el clavel más grande y más bonito se lo ponen al cerdo en el [trasero].” Leyendo aquella frase, por primera vez en dos años, la viuda de Montiel sonrió.
There is further irony in the story. Remember that Montiel had a safety deposit box for which he left no key, and thus it had to be shot at and then exploded in order to open it. This is significative, as it is an allusion to the secrets that Chepe kept from his wife and not she has to tolerate through explosions.
The other irony may be the way in which we see how the widow's life wastes away at the end of the life of Chepe Montiel. It seems as if Chepe carries with him a spirit of destruction towards all that means something.
Yet, the biggest instance of irony in th story is that the widow ceased to lead a normal life after her despot husband died. Montiel's spirit finishes everything that it sees in life and death alike. As a result, his widow becomes aware of the fact that she feels as dead as her husband. It is safe to argue that, as the fortune goes astray, and the memory of Chepe dissipates, so does the spirit of the widow. Hence, Montiel's spirit finalizes her, for good.