VATICAN CITY — Jesus was not born “once upon a time” as in a fable, but in a historically verifiable place and moment that were detailed accurately in the Gospel of Luke, Pope Benedict XVI writes in the third volume of his work, “Jesus of Nazareth.”

Two short excerpts from the pope’s book, which is scheduled to be released before Christmas, were distributed by the Italian publisher Rizzoli Oct. 9, along with an announcement that Rizzoli would present the book at the Frankfurt Book Fair.

Rizzoli said the book fair would be an opportunity to finalize deals for translations of the pope’s book in 20 languages, including English. The Vatican publishing house announced in September that it had made an agreement with Rizzoli to handle the sale of international rights to the book.

The book fair, one of the world’s most important, runs from Oct. 10 to Oct. 14.

Rizzoli also released a facsimile of the book’s cover, which is similar to that used for the first two volumes: The first, published in 2007, covered the period from Jesus’ baptism to his Transfiguration; while the second, regarding his passion and death, came out in 2011.

The pope’s latest literary effort uses the Gospels to explore the infancy and childhood of Jesus.

In a second excerpt released from the new book, Pope Benedict invokes the image of the infant Christ wrapped in swaddling clothes and lying in a manger. He elaborates on an observation by St. Augustine that the manger, where animals find their nourishment, becomes a “reminder of the table of God where man is invited to receive the bread of God.”