The struggle for eternal life as depicted on the Mao Kun Map.

Immortality or eternal life was the state living indefinitely for an infinite or indeterminate amount of time. It was an ability to live forever, or put another way, an immunity from death. In religious contexts, eternal life was often stated to be among the promises by God (or other deities) to human beings who show goodness or else follow divine law (cf. resurrection). Moreover, only God was regarded as truly immortal, hence it is only through God's resources for resurrection and salvation that human beings may transcend death and live eternally.

During the time of Ancient Greece, the boy Melikertes had to escape the wrath of Hera, the queen of the gods. He and his mother jumped off a clif into the sea for protection, becoming powerful as gods. Through his newfound powers, Malikertes learned how to drain people of their souls so he could keep himself young for all eternity. Over the next centuries, he became known as Palaimon.[1] When he he began to study alchemy, the infamous Pirate Lord Henry Morgan devised a way to live forever.[2] The treasure of Corts rendered those who stole from it as immortal skeletons until all the Aztec gold coins were returned and a blood debt repaid.[3] Under Davy Jones, the crew of the Flying Dutchman lived as immortal beings.[4][5] The Fountain of Youth was a legendary spring that restored the youth or grant immortality to anyone who drank from its waters, thereby live forver[5], though at a cost of another's death.[6] For the Fountain, the struggle for eternal youth was depicted on the Mao Kun Map, symbolized by a tug of war between a skeleton and an angel, aligned with the symbol of the Fountainthe Chalices.[7]

In another sense, immortality can also mean being unable to be forgotten by history. For example, Jack claimed that by finding the Fountain of Youth when the legendary explorer, Juan Ponce de Len, failed to do so, he will be remebered throughout time and thus, in a way, never die.

Immortality on Wikipedia

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