So not even 'carved in stone' really means anything?!
Discussion
When you write to your new kingdoms, each in their own language, claiming that their god (each one different) has deemed you to be their worthy leader, then no. A lie carved in stone is still a lie. However, I believe "carved in stone" is more of a reference about not being able to change the past instead of something being "solid as a rock", i.e. reliable.