You can find the Pardoner's Tale here in the original Middle English,
along with a modern translation.
https://sites.fas.harvard.edu/~chaucer/teachslf/pard-par.htm
Many of Chaucer's tales have two or more levels. On the surface, The Pardoner's Tale is a story with clear, direct morals- don't use the name of God in vain, don't play with dice, don't have avarice. Seething beneath this placid surface is a whirlpool of enigmas and strange images. The strangest and most enigmatic is the personification of Death. It is personified here as an undying old man.
The personification of Death is a recurrent theme in Pagan mythology, and it is found many times in Western mythos. For example, the Angel of Death spares the lives of the first-born Hebrew children in Exodus. Here in Chaucer's Christian world it is an old god, a vestige of another age. Instead of appearing in the familiar cowl and bearing a scythe, he comes in the form of an undying old man, representing an old god.
The traditional personification of Death (the guy with the cowl and scythe) would be easier to understand and interpret. In this tale the Old Man wants to keep his identity concealed. We have to glean what we can about him from his cryptic conversation with the three riotoures looking for Death.
One of the reasons I think the Old Man is Death is because the three men go out looking for a person. Not just any particular person- he is carefully specified. He is a privee theef and a false traytour who lives in the next town, because his plague has taken the lives of so many people there.
The first thing the Old Man does when we meet him in the story is tell us something about his life and his condition. He ne kan nat fynde a man, though I walked into Inde... that wolde chaunge his youth for myn age. As we read these lines we realize that this is not an ordinary old man. He has a supernatural power that enables him to leave his old withered body and exchange it for the body of a young man. He can only do this if the young man assents. It is no wonder that no one would change places with his him. Chaucer has us hooked, and we become aware of the mystery of this old man. We follow his words carefully, to see if we can find out anything more about this strange fellow.
He thinks of himself as a captive in his body: thus walke I, lyk a resteless kaityf. In this way he is all men, captive inside their bodies. However, his relationship with Death is a different one than young men have with Death. For the old man says Death ne wol nat han my lyf. No more the privee theef or false traytour, Death is now a liberator who would free the old man from captivity inside the body. The old man would willingly give Death his life, if only he would take it.
The old man is in contrast to the three young men, who fear nothing and are in their prime. They know of a thief who steals the lives of their fellow dice-rollers, but do they know of any of the sentiment this old man expresses?
We find the same idea in the third chorus of Oedipus Coloneus. The endless hours pile up a drift of pain each day; and as for pleasure, when he is sunken in excessive age, you will not see his pleasure anywhere. Later on in the chorus we read of the feathery follies of youth. What could be a more empty folly than to look for Death, in order to slay him?
The old man again expresses his weakness and helplessness when he begs the gamblers to do him no harm. He quotes scripture: Agayns an old man, hoor upon his head, ye sholde arise. The helpless poor old man would then be on his way: I must thider as I have to go. This is a strange line for an old man. He has things he must do, as if he has an important job, or he is under some compulsion. Usually we think of age as a more inactive stage than youth. The Old Man isn't what he seems.
As the story progresses, this guise of helplessness falls away and we realize that the old man isn't helpless after all. He points the way to where the riotoures will find Death. They actually find a trap. If the old man isn't Death himself, he knows where to find him.
In one passage, the old man raps the earth and says, Moder, with yow wolde I chaunge my cheste that in my chambre longe tyme hath be, ye, for an heyre clowt to wrappe me. This passage has strange mixed images of death and repentance. The chest probably refers to a coffin. This chest has been in the old man's chamber a long time without use, and this is the old man's lament. The hayre clowt refers to the cloak people were buried in if they couldn't afford a coffin. However, this cloak wasn't made of hair. People would wear coats of hair to repent for their sins, especially when plague was around. This fits in with the Pardoner's theme of repentance.
There is another personification, that of the earth as leeve moder, or dear mother. Again, this has pagan connotations. It is no wonder that this story has so many pagan images in it, seeing that the Pardoner is involved with selling relics. Relics are a vestige of paganism, in that they are a kind of magic amulet that can perform certain things.
If the three rioters would have looked closely at the old man's speech, they wouldn't have fallen into his trap. They could have realized that they had young bodies, the supreme desire of this Old Man. The Old Man accomplishes his task of finding willing young men to exchange his old body with, for they willingly sell their souls to him for some gold.