Fear, fear of the unknown, fear of being alone & always fear of death & annihilation.
Have gotten these local bible thumpers to do their "big reveal" , its the death card all the way with them, what's going to happen to you in the "after life. Big juju this afterlife deal, the one place where this country rabbi lost his marbles running around condemning people to hell, but in his defense they were pretty apocalyptic times, the disparity between the wealth & poor was night & day, death was literally around the corner.
It can't be as simple as falling like a leaf off a tree, you've served your time on earth,lived your seasons & the time has come, you fall into the last rays of the sunset, fade to black. No, never that simple as it really is, have to have the after life where you can be tortured further or be received home into some blessed tribal communal bliss. And death to you if you did not believe it.
Left alone a castaway on an Island, you could even end up worshipping a soccerball, call him "wilson", the human animal in its aloneness & fear makes up powerful imaginary friends, its only human.

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