"Immortality," Microsoft® Encarta® Online Encyclopedia 2000
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Immortality, unending existence of the soul after physical death. The doctrine of immortality is common to many religions; in different cultures, however, it takes various forms, ranging from ultimate extinction of the soul to its final survival and the resurrection of the body. In Hinduism, the ultimate personal goal is considered absorption into the "universal spirit." Buddhist doctrine promises nirvana, the state of complete bliss achieved through total extinction of the personality. In the religion of ancient Egypt, entrance to immortal life was dependent on the results of divine examination of the merits of an individual's life. Early Greek religion promised a shadowy continuation of life on earth in an underground region known as Hades. In Christianity and Islam, as well as in Judaism, the immortality promised is primarily of the spirit. The former two religions both differ from Judaism in holding that after the resurrection of the body and a general judgment of the entire human race, the body is to be reunited with the spirit to experience either reward or punishment. In Jewish eschatology, the resurrection of the soul will take place at the advent of the Messiah, although the reunion of body and spirit will endure only for the messianic age, when the spirit will return to heaven.