This was an early Gnostic writing that no longer exists. A fourth-century bishop named Epiphanius described it by saying, “The Gnostics have a book which they call the Birth (or Descent) of Mary, in which are horrible and deadly things.”
According to Epiphanius, the book claimed to reveal what Zechariah, the father of John the Baptist, saw in the temple. It said that Zechariah saw the Jewish god in the form of a donkey. At that time, people who criticized Jews and Christians often mocked them by saying they worshiped a donkey god.
This work is disrespectful toward God and is different from the Gospel of the Birth of Mary. The Gospel of the Birth of Mary is a story about Mary’s birth, early life, and marriage to Joseph. It is a legendary tale, but not considered harmful.