One section of the book is called "Virgin Birth - Myth or Historical Truth?"
The Church teaches that Jesus is the son of God and was not conceived through sexual intercourse but by the power of the Holy Spirit, one part of the divine trinity.
In simple language that is at once academic but still easily accessible to a non-specialist readership, Benedict says the story of the virgin birth is not just a reworking of earlier Greek or Egyptian legends and archetypal concepts but something totally new in history.
"It is God's creative word alone that brings about something new. Jesus, born of Mary is fully man and fully God, without confusion and without separation..." he writes.
"The accounts of Matthew and Luke are not myths taken a stage further. They are firmly rooted, in terms of their basic conception, in the biblical tradition of God the Creator and Redeemer," he writes.