I think heaven and hell are man-made concepts devised to scare believers from straying from the "flock", and to scare non-believers into joining the "flock".
During the early stages of Christianity...
"It wasn't until 451, at the Council of Chalcedon that, with the approval of the Pope, the Nicene/Constantinople Creed was set as authoritative. Debate on the matter was no longer tolerated; to speak out against the Trinity was now considered blasphemy, and such earned stiff sentences that ranged from mutilation to death. Christians now turned on Christians, maiming and slaughtering thousands because of a difference of opinion."
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A threat of spiritual death and/or imprisonment was also devised.
"Jesus had more to say about hell than about heaven, and he spoke of hell as a place of punishment where the wicked are "cast," and where the fire is not quenched" (Mark 9:44,47).
"As several modern commentators have noted, hell would be horrible enough if only for the absolute absence of God. But the Bible does not leave the matter there. Our attempts to evade the biblical doctrine of hell weaken our understanding of the Gospel and confuse a world..."
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The same recruiting and retaining methods of reward and punishment are in use today by the Christian church.