On the surface, the title refers to the the Arabic prisoner. This "guest" is one that is thrust upon Daru against his will. Even though the Arab is a prisoner, Daru does not treat him with any hostility and even seems to welcome the idea of his escape. Daru awkwardly...
On the surface, the title refers to the the Arabic prisoner. This "guest" is one that is thrust upon Daru against his will. Even though the Arab is a prisoner, Daru does not treat him with any hostility and even seems to welcome the idea of his escape. Daru awkwardly treats the Arab to coffee after spending a night fretting over the idea that the prisoner might kill him. The idea of death does not seem to bother him nearly as much as the idea of his life being spent to its end in the course a task that he did not even want. This paints a picture of the Arab not as a prisoner but as an unwanted guest whose host is doing his best to be polite. Amidst the overwhelming melancholy, it can be seen as rather humorous.
However, on a more existential level, "the guest" can be thought of as Daru himself. The war of which he wants no part, and by extension the Arab, could be seen as a Host. Daru is a simple schoolteacher. He cares not for the worry of the outside world. This is often met with some degree of skepticism and even hostility from the people around him. Indeed, Balducci seems downright offended that Daru is not happy to accept the assignment. Daru works hard to leave the Arab's fate in his own hands, and in the end, it costs him dearly. He is completely misunderstood and feels utterly alone, surrounded by people completely enraptured in a conflict that contextualizes everything that they experience.
This brings us to the ultimate irony of the title. The original french title "L'hote" can be translated as one who visits or hosts. So while the English title is officially "The Guest," it could just as easily be translated to mean "The Host."