In Greek mythology, Pandora’s jar retained hope after the other troubles escaped. Hesiod’s Works and Days says that the jar contained evils and that only hope remained inside when Pandora replaced the lid.
The Greek word commonly translated as “hope” is elpis. The passage has generated debate because it is not entirely clear whether hope is presented as a blessing protected for humanity or as another troubling thing held back from people. The myth itself does not provide a single explicit explanation of the detail.
The familiar expression “Pandora’s box” is a later version of the story. Hesiod describes a large storage jar, called a pithos, rather than a small box. Renaissance and later retellings helped establish the box image, while the surviving Greek text is the main source for the detail that hope remained inside.