It is Pressfield's first novel taking place in the ancient world since The Afghan Campaign, published in 2006.

In the aftermath of the Crucifixion of Jesus, the office of the Roman governor of Judea receives intelligence of a courier traveling to Corinth with a letter from a religious fanatic calling himself Paul the Apostle.

Fearing a mass uprising, the governor's agents hire the mercenary soldier Telamon of Arcadia, a former legionary of the Legio X Fretensis, to track down the courier and retrieve the letter, in exchange for a substantial bounty and amnesty for the otherwise capital crime he has been arrested for.

Telamon, a peregrinus who refused an offer of Roman citizenship after his enlistment was over, works only for money, but once he tracks down the courier, he undergoes an unexpected conversion and instead determines to protect the courier at all costs and ensure that the letter is delivered.

Publishers Weekly reviewed the book negatively, writing that "Pressfield’s considerable gifts for historical military fiction...are nowhere in evidence in this ponderous account of Greek mercenary Telamon of Arcadia’s mission to preserve and disseminate the gospel of Paul.