American author or two added to religious book (4,5)
I believe the answer is:
mark twain
'american author' is the definition.
'mark twain' can be an answer for 'author' (I've seen this before). I also know that 'american' relates to this answer.
'two added to religious book' is the wordplay.
'two' becomes 'twain' (archaic term for 'two').
'added to' says to put letters next to each other.
'religious book' becomes 'mark' (book of the Bible. I am not sure about the 'religious' bit.).
'twain' put after 'mark' is 'MARK TWAIN'.
'or' is the link.
Can you help me to learn more?
(Other definitions for mark twain that I've seen before include "Tom had him writing about?" , "US writer" , "Creator of Tom Sawyer and Huckleberry Finn" , ""The Adventures of Huckleberry Finn" author" , "American humorous writer, d. 1910" .)