("The Great Event") is a tract in Nahuatl comprising 36 pages and was published in Mexico City, Mexico in 1649 by Luis Laso de la Vega, the vicar of the chapel of Our Lady of Guadalupe at Tepeyac outside the same city. In the preface Luis Laso de la Vega claimed authorship of the whole work, but this claim is the subject of an ongoing difference of scholarly opinion. The tract is written almost entirely in Nahuatl and includes the , which narrates the apparitions of Our Lady of Guadalupe at Tepeyac in 1531. It also includes the , which enumerates the miracles attributed by some; Luis Laso de la Vega does not mention either him or Antonio Valeriano as authors. The traditions recounted in the 1649 tract were first published in the Spanish book ("Image of the Virgin Mary, Mother of God of Guadalupe"), written by Miguel Sánchez in 1648 and being a theological dissertation linking the Guadalupan Image to . There is an equally contentious and much shorter manuscript in Nahuatl preceding the , which is titled the ("This Is the Great Marvel"), also known as "The Primitive Relation" of the apparitions. It is in The National Library of México. Sections Preface The first section, a preface, is titled in Nahuatl "Noble Queen of Heaven, Forever Virgin, Mother of God". In it Lasso addresses the Virgin directly, and after an introduction of four to five lines proceeds to the reason why he took up Nahuatl in order to publish the history of the apparitions: "You yourself spoke in Nahuatl to a poor Indian and painted yourself in his , thus showing you are not displeased with many languages". "That the Indians of this land remember and keep in their language all you did for them and how it happened". "Christ on the Cross had His sentence in three languages". "You were with the apostles in Pentecost to receive the Holy Spirit" (a remembrance of the miracle of Diaspora Jews understanding each in his own language ) The preface ends with a short prayer in two lines pleading the Virgin's intercession for the assistance of the Holy Spirit in writing in Nahuatl. The second section, the ("Here Is Recounted") constitutes the narrative in Nahuatl of the apparitions, including the Virgin's apparition to St. Juan Diego's uncle Juan Bernardino. It is probable that the Nahuatl manuscript used by Lasso was