One of Death's origins is Odin, the Germanic All Father. Also in Christian belief, Death is a harvester of souls, that's why he has a scythe.
The old man with a scythe in "The Pit and the Pendulum" symbolizes death and the passage of time. The scythe is often associated with the Grim Reaper, a personification of death in folklore and literature. In the story, the old man's presence adds to the narrator's feeling of impending doom and mortality.
Grim Reaper
A pendulum suggests a sense of balance, rhythm, and predictable back-and-forth motion. An old man with a scythe typically represents the passage of time, mortality, and the concept of death.
The rioters mockingly refer to Death, but end up encountering and giving him the old man. The old man was initially looking forward to meeting Death but ends up fearing the rioters instead. This irony highlights the unpredictability and inevitability of death, showing how attitudes towards it can change in unexpected ways.
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DEATH DEATH
An old man was wandering around town either trying to find death or to trade his age for youth. The man said that the three could find death under a tree in a grove.
The attitude that the old man has toward death is ironic for a couple of reasons. One of these ironies is that the man wishes he had more time in his life.
They wanted to find death to kill him for killin there friend.
In "The Pardoner's Tale" the old man's attitude toward death is said to be ironic. The irony is that he is cheerful toward the idea of death, which is the opposite of what one would expect.
The term "old man" is a colloquial way to refer to one's father and likely originated as a term of endearment or familiarity. It is a common way some individuals refer to their father in informal settings.