In this paper, it is argued that The Life of Mary the Younger, an anonymous Byzantine text of the eleventh century, has a conscious intertextual dialogue with the oldest Byzantine Life venerating a holy woman, the Life of Macrina written by her brother, Gregory of Nyssa, between 380 and 383. The intertextual relation between these two female Lives takes the form of parody. Following Linda Hutcheon’s theory of parody, this article shows how the anonymous hagiographer of Mary reworks Gregory’s authoritative text to create a new work, a parody in terms of postmodern literary criticism, whose aim was to criticise old and contemporary customs, conventions and ideologies. In other words, the present article approaches and decodes the literariness, the function and ideology of Mary’s Life in the light of Macrina’s Life.