The Bible comes out ahead on sales.
Previous posters link bears that out.
But if we can leave the subject matter out of it
(on here...am I kidding?).
I have an interesting observation.
Been going around 2nd hand book shops since 1981.
2nd hand Bibles are everywhere. Some shops had a shelf full of 2nd hand Bibles.
Never seen 1 copy of the Koran in a 2nd hand book shop. Never.
So before posting this I checked out ebay.
"Koran + book" pulled up 74 entries. "Bible + book " pulled up 8,615 entries.
So narrowed it down.
"Koran + Used Book" = 5 entries. "Bible + Used Book" = 207 entries."
Make of it what you will.
But it appears that readers of the Koran tend to hold onto their copies,
whilst readers of the Bible tend not too.
Of course more copies of the Bible have been printed than the Koran
so one would expect to see more 2nd hand copies.
But that previous link listed other books that have sold over a
100 million copies - Lord of the Rings, Tale of two Cities etc
These too are standard 2nd hand fare and are often seen in
The Koran has sales over 800 million. So if it was a 'normal' book
registering those numbers you would expect to see at least 2 or 3
per 2nd hand book shop.
I have never seen one.
Just an observation.
I cannot state that one is better than the other as I have only
read the Bible.