The two clergy must battle to restore DAMON and purge Satan from the enslaved AI's core."
That is how the book is introduced on smashwords.
Salvatore has a great deal of inner pain and doubt he must overcome, he felt betrayed by his Church. Benito, much younger, deals with the tech aspects and follows in the steps of his Lord.
Diabolus, one of my favorite books for 2014, will provide several hours of enjoyment for the Scifi lover, as well the person interested in Spiritual and Christian concepts.
Disclosure: I am not a member of the Roman Catholic church.