Historians accept the Gospels as generally credible for four reasons: First, they are first-generation books, written while eyewitnesses were still alive. Secondly, multiple witnesses exist: four Gospels, not just one. Third, what the Gospels say is supported by other parts of the New Testament, all by authors who wrote independently of one another. Finally, the Gospels are corroborated by other evidence, including ancient writings—Jewish, Greek, and Roman—and archeological discoveries.