Corpse.
A corpse is the source of the most severe conceivable ritual pollution in the Hindu worldview (ashaucha).
Despite the fact that Hindus embrace death as an unavoidable part of life, the risks posed by a body cannot be overlooked.
Both to protect the living and to assist the departed in making a peaceful transition to the next world, the dead corpse must be treated properly.
As a result, the final rituals (antyeshthi samskara) begin on the actual day of death.
The cremation of the dead corpse is one of the oldest of these rituals, since the impurity will continue to harm people around the body until it is destroyed by fire.
The removal of a possible host for wandering spirits, who, according to popular belief, may reanimate a body, is a second rationale for rapid cremation.
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