Analysis of the probability Matthew, Mark, Luke, John authored or dictated the canonical gospels.
| Gospel | Evidence for authorship by apostle or evangelist | Alternative explanation | Probability the gospel was written or dictated by the person the gospel is named after |
| Gospel of Mark | Mark is identified by Bishop Pappias in late first/early second century as a secretary to the apostle Peter and the author of a gospel. It is improbable Church leaders would randomly name a canonical gospel after a low-ranking and obscure Christian. | Pappias was confused about what he was told by people who knew the disciples of Jesus. Pappias was referring to a different Mark, not the Mark of the canonical gospel. | More probable than not |
| Gospel of Luke | Luke is identified by Bishop Iranaeus in mid to late second century as author of the gospel of Luke. It is improbable Church leaders would randomly name a canonical gospel after a low-ranking and obscure Christian. | First surviving attestation for the authorship of Gospel of Luke is about 100 years after it was written, reducing the reliability of this attestation. | As probable as not |
| Gospel of Matthew | Matthew is identified by Bishop Pappias in late first/early second century as an author of an Aramaic-version of a gospel. | Even if Matthew wrote an Aramaic-version of a gospel, Greek translators in the late first century or second century could have completely re-worked it. | As probable as not |
| Gospel of John | Bishop Iranaeus in mid-second century was told by Polycarp (a disciple of the apostle John) that John authored a gospel. That makes Iranaeus only one person removed from a disciple of Jesus. | Iranaeus could have been confused about what Polycarp told him, or it could have been a different John, not the apostle John, who authored the canonical gospel. | Probable |