so long as it happened within a minute or 10 rounds of combat yes

*Adding to all my loot pools*

Diamond worth 299gp

The DMs ive worked with have not cared about normal components, BUT do care about components that are consumed, which revival spells consume that diamond component

What if they repeatedly had gentle repose cast on them for all those years? 

would you be able to use it on a decapitated person if you sewed their head on

Have your BBEG cast this on your party members. “You do not have my permission to die”

Using this for a coffeelock, restoring 1 level of exhaustion

A skill that awakes the enemy spirit and is now under your command but with three constitution throws if all three fail it does not work but if the spell does work it can make there spirit your's

so theoretically if someone was turned into a vampire about 30 seconds ago, would casting this being them back 

It says I "can't return to life a creature that had died of old age." So if I attempted to do so, would I waste my spell slot and material components?
Also a question, does the soul have to be free and willing for this spell to work (like with Resurrection) or can I use this on anyone