Nano-technology - Not Sufficiently Advanced, as per the Arthur C. Clarke gold standard of sufficiently advanced technology.
The proper names and descriptions of a sword’s parts.
While we’re talking about the subject of constructing religions, I’d like to bring up the concept of the Creed. The creed is nothing more than a simple statement of the religion’s beliefs, meant to be recited. If you cannot write a creed for your monotheistic religion, it probably needs work on internal consistency. Creed examples:
The court wizards of Angolterre have been working for several generations to protect the dynasty. They see to it that the new monarch's names acronymically refer to a rune of protection. Once completed, the rune will make the dynasty almost invulnerable in battle, wise in counsel, etc. Unfortunately the next name, the only one that starts with the right letter, happens to have belonged to the worst monarch in living memory. Not much chance of getting the current ruler to name his child that, or for the people to put up with it if he did! What's a court wizard to do? The magic requires that the plot be kept secret of course...