Discussion of the afterlife is largely absent from Jewish religious discussion today, but for a long time the concept of postmortem reward and punishment was an important part of Judaism. Elon Gilad traces these ideas from their biblical origins and explains how they changed and developed. It seems that they key moment for cementing belief in the afterlife came around the first century CE, as Gilad writes (free registration required):
According to Josephus, a Jewish historian writing at the end of the first century CE, the question of afterlife was a major point of contention for Jewish theologians of the period. The Sadducees, the prominent priestly class who ran the Temple, did not believe in an afterlife, or in the resurrection of the dead, Josephus writes. Meanwhile, their counterparts and adversaries, the Pharisees, an elite of experts in Jewish law, believed in both.
Once the Temple was destroyed in 70 CE, the Sadducees and their theology were lost, and the Pharisees and their conception of the afterlife became mainstream rabbinical Judaism.
Thus, from the time of early rabbinic Judaism, belief in the afterlife and the resurrection of the dead became core to the faith. “All Israel have a portion in the world to come,” the Mishnah (200 CE) states, only to qualify this statement with a list of individuals who are excluded: “One who maintains that resurrection is not a biblical doctrine, the Torah was not divinely revealed, and a heretic.”
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