A specific and unusually vivid category of Egyptian evidence for belief in the akh survives outside the formal funerary corpus entirely: letters written by the living and left at tombs, addressed directly to a named deceased relative's akh, asking for help against illness, legal trouble or a hostile rival, or sometimes complaining that the akh's own inattention or hostility was the cause of the writer's misfortune in the first place. These letters to the dead treat the addressee as a real, reachable agent, capable of intervening in the affairs of the living, which is precisely the capability the akh state was believed to confer and the ka and ba, on their own, were not.
The existence of this correspondence shows that the transfigured akh was not, for ordinary Egyptians, a purely theological abstraction confined to royal funerary texts; it was a practical category with consequences for everyday family and legal life, an ancestor who had become an akh was someone whose favour was worth cultivating and whose displeasure was worth fearing, not unlike a powerful living relative.
The akh's capacity to act for good or ill also explains a recurring feature of Egyptian magical and protective practice: spells and amulets exist specifically to guard the living against hostile akhu, plural, alongside spells meant to help the newly dead achieve akh status successfully, treating the transformation itself as something that could go wrong and produce a dangerous rather than a beneficent spirit.