[Francis] gave the desk a final kick and turned to glare impatiently at the skull: Why don't you grin at something else for a change? (2.16)
Skulls always serve to remind us of death, and two of them bookend this novel. We see the first one here. Ironically enough, Francis's skull will make its cameo at the novel's conclusion.
And the hate said: Let us stone and disembowel and burn the ones who did this thing. Let us make a holocaust of those who wrought this crime, together with their hirelings and their wise men; burning, let them perish, and all their works, their names, and even their memories. Let us destroy them all, and teach our children that the world is new, that they may know nothing of the deeds that went before. (6.11)
Two ideas for the price of one quote? Nice. First idea: notice how it's the "hate" saying these things, not the simpletons? This tiny detail points to a mass mental state controlling this era of death and violence. Second: people die, but they generally hope their works—artistic and scientific—will grant them a sort of life after death. A sort of immortality. Here, that idea gets the same "dust in the wind" treatment as everything else. Nothing lasts.
Brother Sarl finished the fifth page of his mathematical restoration, collapsed over his desk, and died a few hours later. Never mind. His notes were intact. Someone, after a century or two, would come along and find them interesting, would perhaps complete his work. Meanwhile, prayers ascended for the soul of Sarl. (8.4)
Depressing and morbidly funny, Sarl's death is probably the happiest in A Canticle. There's hope someone will come along and complete his work, but if nothing else, he at least has people praying for his soul. No one receives better in the whole novel.
After a while he entered the forested area. The buzzards were busy at the remains of a man. The wandered chased the birds away with his cudgel and inspected the human remnants. Significant portions were missing. (11.87)
Our first protagonist's death is discovered by the wanderer, concluding part one with a reminder of mortality. This isn't Pirates of the Caribbean, folks. Even the main characters die. So we guess it might be A Game of Thrones.
There were signs of progress in the world, and the village of Sanly Bowitts had achieved the fantastic literacy rate of eight per cent—for which the villagers might, but did not, thank the monks of the Leibowitzian Order.
And yet [Dom Paulo] felt forebodings. Some nameless threat lurked just around the corner of the world for the sun to rise again. (13.29-30)
We're willing to bet death is the "nameless threat" in this quote. It can be the best of times, it can be the worst of times, but death isn't one for vacations. Well, maybe working vacations.
The buzzards strutted, preened, and quarreled over dinner; it was not yet properly cured. They waited a few days for the wolves. There was plenty for all. Finally they ate the Poet. (23.21)
Again, we've got the death of a character ending a section. Miller's novel is like some kind of macabre carnival of death clowns; nobody gets out alive.
Generation, regeneration, again, again, as in ritual, with blood-stained vestments and nail-torn hands, children of Merlin, chasing a gleam. Children, too, of Eve, forever building Edens—and kicking them apart in berserk fury because somehow it isn't the same. (24.24)
The themes of "Mortality" and "Time" share the stage in this singsong marching tune. No matter how many generations come, go, struggle, or die, the ideal of a perfect society, an Eden, is never reached.
It was a troubled night, a night that belonged to Lucifer. It was the night of the Atlantic assault against the Asian space installations. In swift retaliation, an ancient city died. (25.172-173)
As we discuss in our "Symbol, Imagery, Allegory" section, the novel's use of "Lucifer" connects the ideas of evil, knowledge, and technology in A Canticle. Here, Lucifer links these notions to death, by way of nuclear weaponry. Of course, if anything deserves all of those negative associations, all at the same time, it would probably be nuclear weapons. They're nasty buggers.
She still said nothing. He blessed them and left as quickly as possible. The woman had handled the beads with fingers that knew them; there was nothing he could say to her that she didn't already know. (28.37)
This powerful scene shows a woman struggling with her child's mortality in the face of society's laws, God's laws, and her own fears and desires. Perhaps this is a scene better felt than analyzed. Boom.
That inky Dark—gulf between aham and Asti—blackest Styx, abyss between Lord and Man. Listen, Jeth, you really believe there's Something on the other side of it, don't you? Then why are you shaking so? (29.56)
Aham is Sanskrit for "I", and asti translates to "am" or "existence." So that gulf making Zerchi shiver is what separates himself from his true existence. Hamlet's undiscovered country exists in a similar dark gulf, and impending death gives both characters a really excellent view of it.