What does the Gentle Repose spell do that allows Raise Dead-type spells to work later?

Question

I got into an odd debate and now Im wondering exactly how gentle repose is supposed to work in game.

So it started when I asked if gentle repose would increase the length of time it was possible to create a soul gem for the purpose of the soul-powered magic feat.

They ruled that no, gentle repose does nothing as it makes no mention of keeping the soul around and that in the magic rules about bringing back the dead state that when a living creature dies, its soul departs. So I went looking into raise dead and breath of life to see how they differed. I was surprised that both were conjuration(healing). I was expecting that breath of life would make some mention to the soul still being around which was why it had a limited time frame in which it could work. No such luck.

So it got me wondering what gentle repose does thats different from make whole (assuming that the dead do count as objects), repair undead, and restore corpse, except of course that gentle repose specifically states it prolongs the timeframe in which raise dead type spells work.

But why and how? I originally assumed it kept the body fresh and the spirit near, but the condition of the body doesnt seem to matter much as long as its present and mostly intact.

I had asked a question about if gentle repose worked to prolong breath of life being usable. The only answer didnt really solve it.

Answer 1

I don't think it is possible to plainly justify Gentle Repose effects without making speculations about how the universe works. However, there are several points in the rules which can help us to explain it without going too far in conjectures.

About the soul of the dead creature :

As it is stated in your link about bringing back the dead, without special actions to prevent it, the soul of the creature departs its body when it dies.

Raise Dead description mentions that (in normal conditions) the soul of the creature comes back from wherever it went when restored to life:

In addition, the subject’s soul must be free and willing to return.

Finally, Gentle Repose is only dedicated to Raise Dead spell, the wording of the description is pretty clear about it :

Doing so effectively extends the time limit on raising that creature from the dead (see raise dead).

For this point, it seems clear that Gentle Repose does nothing related to the soul of the dead creature, it only affects its body (and it confirms you cannot use this spell to increase the length of time to create a soul gem).

About how Gentle Repose distinguishes from other spells:

The main difference between Gentle Repose and the other spells you mention is that Gentle Repose prevents the decay of the body, where the others repair/heal the damages due to decay (or other inconveniences damaging the body).

As you can see in the Raise Dead description, there is no requirement about the state of the body. The target must be the dead creature touched and that's all. Therefore, what seems to be important here is not the state of the body, but the time since it is dead/decaying. This would justify why, by preventing the decay, Gentle Repose works, when the other spells just repairing the damages don't extend the time limit of Raise Dead.

The exact justification of the relation between the time since the creature died and its corpse decaying is however nowhere to be found and would be open for interpretation.