Why does Montresor end his story with the latin phrase meaning "May he rest in peace"? "The Cask of Amontillado" by Edgar Allan Poe
This final phrase, which actually means "rest in peace," not "may he rest in peace," provides another hint that this story is a deathbed confession narrated by Montresor fifty years after the fact. While we as readers don't know with certainty that Montresor is speaking to his priest, he addresses someone he says knows the "nature of his soul." Who better than a priest to know that?
If it is a deathbed confession, it means that the murder has weighed on Montresor all these years, despite his assertions while telling the tale that Fortunato deserved his fate. That guilt assails him as he speaks is suggested when he notes that as he walled up his enemy his heart "grew sick." He attributes this to the dampness of the catacombs, but the reader feels it is what he has done--a horrible murder walling up someone alive--that makes his "heart" (not his lungs or some other body part) sick.
By saying "rest in peace" at the end of the story, Montresor indicates that his desire for revenge is over and that he no longer wants Fortunato to suffer. He hopes his former enemy is at peace. While it is possible the words are ironic or sneering, the tenor of the language and the commentary of the last paragraph indicate Montresor speaks sincerely. After all, the murder has left him heartsick and he "hastens" to finish his task. But what makes Poe interesting is the ambiguity with which he leaves the reader: we can argue about what the ending means and whether or not Montresor truly repented of his deed.
Montresor concludes with "In pace requiescat" in order to put the "period," so to speak, at the end of his tale of revenge. His is the wine connosieur's vendetta:
At length I would be avenged; this was a point definitively settled--but the very definitiveness with which it was resolved precluded the idea of risk. I must not only punish with impunity. A wrong is unredressed when retribution overtakes its redresser. It is equally unredressed when the avenger fails to make himself felt as such to him who has done the wrong.
This last line underscores the intentions of Montesor to avenge himself against Fortunato. Cleverly, Montresor plans out his revenge step by step until its fruition. In fact, he enjoys himself in his revenge, delighting in the details of placing the flambeaux in certain positions to create shadows, etc. He toys with Fortunato's ego, telling him, "We Will go back; you will be ill, and cannot be responsible."
With the mason's trowel, Montesor has more fun with mind tricks, making puns on the word mason. So, when he finally walls in Fortunato, he feels that he has accomplished his artistic plan of revenge and takes pride in his accomplishing this crime without retribution for fifty years, punctuating his tale with the Latin phrase that signals his pride in his revenge.
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