It's an individual Jew's ultimate reward, but the nature of the World to Come has always been disputed.
The idea that the soul is the human instrument of spirituality became more prominent over the course of Jewish history.
The Transmigrating Soul. Jewish Reincarnation. Jewish Life After Death. Jewish Afterlife and Eschatology. Jewish View on Next Life. Jewish Ideas and Beliefs
Everlasting life was not always guaranteed to the Jewish soul.
Amending prayers that mention resurrection to accord with modern sensibilities.
By the second century at the latest, belief in resurrection had entered Jewish liturgy and legal writing.
When and how will the dead will be brought back to life?