 It is widely accepted that this was the first gospel (Marcan Priority) and was used as a source by both Matthew and Luke, who agree with each other in their sequence of stories and events only when they also agree with Mark.Since about 1950 there has been a growing consensus that the primary purpose of the author of Mark was to announce a message rather than to report history.The idea that the gospel could be used to reconstruct the historical Jesus suffered two severe blows in the early part of the 20th century, first when William Wrede argued strongly that the "Messianic secret" motif in Mark was a creation of the early church rather than a reflection of the historical Jesus, and in 1919 when Karl Ludwig Schmidt further undermined its historicity with his contention that the links between episodes are the invention of the writer, meaning that it cannot be taken as a reliable guide to the chronology of Jesus' mission