. . "The Secret Gospel of Mark is a putative non-canonical Christian gospel mentioned exclusively in the Mar Saba letter, a document of disputed authenticity, which describes Secret Mark as an expanded version of the canonical Gospel of Mark with some episodes elucidated, written for an initiated elite.In 1973, Morton Smith, a professor of ancient history at Columbia University, reported having found a previously unknown letter of Clement of Alexandria in the monastery of Mar Saba on the West Bank transcribed into the endpapers of a 17th-century printed edition of the works of Ignatius of Antioch. "@en . .