Entertaining mystery, but not my type of book

I found the book to have some rather humorous, whimsical parts that I could not understand whatsoever. The jokes didn't really resonate with me, and I didn't find it funny at all. The plot itself was pretty solid, a person mysteriously found dead, and another person having to try to understand their way of thinking in order to solve the murder case before being killed by the murderer (of Jerusalem). Ultimately, I found it so boring that I couldn't finish it. The book was very old timey. I don't know who William Blake is - maybe I would have understood the book more had I read that guy's book. While the murder mystery was nice, the book was not "rollicking" as the cover says, it was boring, like the author tried to come off as funny but failed.
The writing style was ehhhh, not too good, not too bad. While it was pretty vivid, it wasn't anything exceptional either. Overall, 3/10. Some people might like it, but I do not.