Witch trials are common enough in the Kingdom and few who stand accused have any hope of escaping the hangman, despite the fact that it is rare for the accused to have any real magical power, malign or otherwise.
Intrigues and adventures within the glittering courts of the land’s nobility: A collection of Tales of Adventure
When you sleep, your soul briefly returns to the place where it was created/goes to when it dies, and seeks nourishment. Everybody's soul is created with a little link (or you could say a greater entity calls it back) to that place so that it can return easily, but upon death, the soul returns via that and annihilates the link as if returns.
Also, as an added thingy, you could say the entity supplying the link, or residue of the links themselves, (whichever) is the source of all arcane power.