I nominate
Ben-Hur: A Tale of the Christ by Lewis Wallace.
The best-selling American novel of all time. - Amazon
General Lew Wallace's Ben-Hur vividly reimagines the mighty Roman Empire and the rise of Christianity. The saga of Judah Ben-Hur's spiritual journey from slavery to vengeance to redemption is both a vivid historical adventure and a powerful story of one man's religious awakening. As Blake Allmendinger writes in his Introduction to this Modern Library Paperback Classic, "Ben-Hur has endured for more than one hundred years because it offers something for everyone. The story of the Jewish hero Ben-Hur, his conflict with the Roman warrior Messala, and his conversion to Christianity at the foot of the Cross, combines adventure, sentimentality, athletic spectacle, and religious devotion." - from the inside flap
Kindle - free
https://www.amazon.com/dp/B004UJ10U6
https://www.amazon.com/Ben-Hur-Illus...dp/B01FFYCMMO/
Kobo - 99 cents
https://store.kobobooks.com/en-us/eb...-the-christ-36
B&N nook - 99 cents
http://www.barnesandnoble.com/w/ben-...ace/1100059503
http://www.barnesandnoble.com/w/ben-...ace/1113673095