Algernon Blackwood 
The Human Chord (Annotated) [EPUB ebook] 

"WANTED: A secretarial assistant with boldness and imagination, according to a retired clergyman. Single; unworldly; tenor voice and some understanding of Hebrew required. Make use of Philip Skale." Robert Spinrobin was desperate for work, so he accepted the challenge, taking the bait entirely. "Unworldly" lit the match, and he burst into flames. He looked to have the other requirements, as he had a thin tenor voice that was not unmusical, as well as a smattering of Hebrew that he had picked up at Cambridge because he enjoyed the fine, high-sounding names of deities and angels found in that language. He grouped courage and imagination with the rest of them. He would come to regret his dare.