Prometheus is Pandora’s husband’s brother and warned him not to accept Zeus’s gifts.
Prometheus and Epimetheus are brothers in Greek mythology. Their names form a contrast often explained as forethought and afterthought. Prometheus recognizes the danger of Zeus’s gift and advises Epimetheus to reject it, but Epimetheus accepts Pandora when she arrives.
The warning is part of the larger conflict between Zeus and Prometheus. Prometheus steals fire for humanity, and Zeus responds by arranging Pandora’s creation and sending her to the mortal world. The story links the theft of fire, Pandora’s arrival, and the spread of human troubles into one mythic sequence.
Prometheus is not Pandora’s husband and does not open the vessel. Those roles belong to Epimetheus and Pandora respectively. Later retellings sometimes simplify the family relationships, which can make the two Titan brothers easy to confuse.