Verdi and atheism

In the question posed in the previous post regarding atheist composers one I did not list was Verdi. I am not an expert on Verdi at all - regretably due to lack of time not due to an extremely great interest in his music. I however found the following reference on the net regarding a letter by his wife:
'Elsewhere, Giuseppina wrote: "He is a jewel among honest men; he understands and feels himself every delicate and elevated sentiment. And yet this brigand permits himself to be, I won't say an atheist, but certainly very little of a believer, and that with an obstinacy and calm that make me want to beat him. I exhaust myself in speaking to him about the marvels of the heavens, the earth, the sea, etc. It's a waste of breath! He laughs in my face and freezes me in the midst of my oratorical periods and my divine enthusiasm by saying 'you're all crazy,' and unfortunately he says it with good faith."' http://www.daylightatheism.org/2008/05/the-contributions-of-freethinkers-i.html
This clearly puts Verdi close to atheism.
The aesthetic significance of this issue will be looked at in future posts. However as a search on google for 'atheism in music' currently yields only 113 pages it is clearly an underexplored issue.