...can Keltham divide the knowledge into two portions, such that it's only dangerous when two clerics combine the pieces?
...doesn't seem like the sort of thing you could do with the equations underlying antimatter - no, wait, he's being dumb.
"Please get me a book, any book, that wouldn't look at all out of place or unusual in that Iomedan cleric's home library, preferably without anybody else observing which book you have. And having the cleric here in half an hour, instead of ten minutes, is fine, because I need to write things down anyways. With very strong guarantees about nobody watching me writing."