In Hesiod’s Works and Days, Prometheus warned Epimetheus not to accept Zeus’s gift.
Prometheus is a Titan associated with intelligence and forethought. In the wider myth, he becomes humanity’s advocate and steals fire from the gods, an act that brings Zeus’s retaliation. Pandora’s arrival is presented as part of that retaliation.
Hesiod says Prometheus cautioned his brother Epimetheus against accepting anything from Zeus. Epimetheus nevertheless accepted Pandora, who had been sent as a divine gift. The warning creates the story’s central contrast between foresight and afterthought.
Prometheus is sometimes incorrectly named as Pandora’s husband or as the person who opened the jar. In Hesiod’s account, he is her husband’s brother and the earlier opponent of Zeus. Those relationships help explain why the Pandora episode follows the Prometheus myth.