Okay, I wasn't quite sure about what I had written earlier, so I've spent the last hour or so researching the topic of character status.
Here's what I've found:
Characters that are reduced to 0 to -10 hit points during combat are given status "dying" and at end of combat, they are auto-bandaged, putting them at 0 hitpoints and giving them the staus of "unconscious". Unconscious characters can be healed by spell, effect or rest.
Outside of combat, if a character is reduced below 0 hitpoints, they are given status of "dead" and can only be brought back with a resurrection spell.
To sum up, I was wrong above.
But, combat still works the same way- you've got to do more damage than would kill them, to actually kill them.
As for what spells the temple has, that is definable by the designer, so you don't have to give them that spell.