I recently finished reading "A Severe Mercy" by Sheldon Vanuaken.
I read some of the book on an Airplane over the Atlantic. The drone of the engines and the monotony of the travel was so distinctly contrasted to the fluid and poetic writing.
I cried for an hour in the little green yard of a church in Eastern Turkey. I wasn't upset or having an emotional breakdown... the book was so beautiful and so sad. It was carthartic in the truest sense. And yet as I continued over the next few pages I'd still get teary.
Finally at home I finished... having taken breaks to think through what he had said. The sadness was good, and the sadness had an ultimate good. The author didn't realize it at first, but later, walking through life he saw the purpose. 'How true' I thought.