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‘What is Christianity’: A reader’s guide to Benedict XVI’s last book

‘What is Christianity’: A reader’s guide to Benedict XVI’s last book

Benedict XVI’s final work, “What is Christianity,” was officially launched on Jan. 20, weeks after his death at the age of 95.

The book, so far only available in Italian, has attracted a lot of attention, and  not only because it gathers the final writings of one of the greatest theologians of the modern age.

The book is also being discussed because of reports that the late German pope only wanted the essays to be published after his death, because of the “murderous clamor” that surrounded the publication of other works after his resignation in 2013.

Media attention has focused as well on Benedict’s reference to “homosexual cliques” in seminaries, in an essay on the clerical abuse crisis, which was previously published in 2019.

What does the new book say? And how original are its contents? The Pillar takes a look.

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A chapter-by-chapter guide


Elio Guerriero, the Italian director of the theological journal Communio, explains the genesis of the book. Having previously collaborated successfully with Benedict XVI on a volume about Jewish-Christian dialogue, he encouraged the pope emeritus to publish a book of his writings since his resignation. Benedict XVI said that he would think about it.

Benedict was then disturbed in 2020 by the controversy surrounding his contribution to a book on priestly celibacy overseen by Cardinal Robert Sarah, Guerriero wrote

But in a letter to Guerriero dated Jan. 13, 2021, Benedict said that he wanted to have his post-resignation works published — but only on condition that they appeared after his death. “The fury of the circles that oppose me in Germany is so strong that the appearance of the slightest word of mine immediately provokes a murderous uproar on their part,” he wrote.

Benedict set to work revising the texts, including extending his previously published reflection on the priesthood. He expressed great satisfaction with the essay during a meeting with Guerriero on June 28, 2021, on the eve of his 70th ordination anniversary.

To give the collection a more complete feel, Benedict wrote additional pieces on non-Christian religions and on the Eucharist. While the texts were originally written in German, Guerriero translated them into Italian, which Benedict wanted to be the reference language.


In a brief preface dated May 1, 2022, Benedict explains that he did not intend to write anymore after stepping down as pope, but slowly took up his pen again after Francis’ election. He then gives a brief overview of the book’s six chapters. He says that he wrote the works at the Mater Ecclesiae Monastery, his retirement residence in the Vatican Gardens, and entrusted their publication to Guerriero because the Italian author wrote a biography of him and is known for his theological expertise.

Chapter 1

Entitled “Religions and the Christian faith,” this chapter opens with a text called “Love at the origin of the mission.” The text consists of a lecture that Benedict gave on Oct. 21, 2014, marking the inauguration of the great hall of the Pontifical Urban University, which had been renovated and named in his honor. It is presented unchanged.

Benedict then adds another brief text called “What is religion,” whose purpose, he says, is to clarify the concept of the religions with which Christianity seeks to enter into dialogue. It was completed on March 19, 2022, and has not been published previously.

Chapter 2

Entitled “Fundamental elements of the Christian religion,” this chapter addresses the nature and future of monotheism. It opens with an essay, completed on Dec. 29, 2018, called “Monotheism and tolerance,” which some commentators consider the book’s highlight.

In the text, Benedict laments “the growing intolerance exercised precisely in the name of tolerance” in Western societies. “The intolerance of this apparent modernity towards the Christian faith has not yet turned into open persecution. But it presents itself in an ever more authoritarian manner, aiming to achieve, with the legislation that follows, the extinction of what is essentially Christian,” he writes.

The essay is followed by a brief reflection on what Benedict sees as the shortcomings of many efforts at dialogue between Muslims and Christians. The text, entitled “The Christian-Islamic dialogue,” was finished on March 1, 2018, but not published until now.

Then comes “Music and liturgy,” a text composed by Benedict XVI on the occasion of receiving an honorary doctorate from the Pontifical University of John Paul II and the Academy of Music in Kraków, Poland, at Castel Gandolfo on July 4, 2015.

This is followed by “Theology of the liturgy,” a preface that Benedict wrote for the Russian edition of the 11th volume of his complete works. The text was finished on July 11, 2015.

Chapter 3

Entitled “Jews and Christians in dialogue,” this chapter opens with the long essay “Grace and Vocation without Remorse: Comments on the treatise De Iudaeis,” inspired by a book by the theologian Franz Mußner “about the enduring positive meaning of the Old Testament.” The text was completed on Oct. 26, 2017, and published in the July-August 2018 edition of the journal Communio.

The essay is followed by an exchange of letters between Benedict and Rabbi Arie Folger, the Chief Rabbi of Vienna, Austria, in August and September 2018, reflecting on the themes raised by the Communio article. The letters were previously published in Italian in the 2019 book Ebrei e Cristiani, the collaboration between Benedict and Elio Guerriero.

Chapter 4

Entitled “Topics of dogmatic theology,” this chapter opens with an interview with Benedict conducted by the Jesuit Fr. Daniele Libanori (now an auxiliary bishop of Rome). The exchange, titled “Faith is not an idea, but life,” took place to mark a Rome symposium on justification by faith in 2015. The text was published in L’Osservatore Romano on March 16, 2016, translated into Italian by the Jesuit Fr. Jacques Servais. It also appeared in Libanori’s 2016 bookPer mezzo della fede.” Benedict says that his aim in the interview was to explain how we can comprehend the suffering and death of Jesus Christ today.

That is followed by a substantial essay called “The Catholic Priesthood,” a reworked version of the text published in Cardinal Sarah’s 2020 book “From the Depths of Our Hearts.” Benedict says he aimed to give the text a “new center of gravity,” filling in what he believed was a gap in Vatican II’s text on the priesthood, Presbyterorum ordinis. The revised and expanded text was completed on Sept. 17, 2019.

Next is a text called “The meaning of communion,” in which Benedict addresses the debate on intercommunion between Catholics and Protestants, which, he notes, flares up from time to time in his native Germany. He reflects on the Eucharistic life of the Catholic Church today, discerning a “very advanced Protestantization of the understanding of the Eucharist” in some quarters where calls for intercommunion are also particularly loud. He suggests that true ecumenism requires an honest recognition of the deep differences that remain over the Eucharist between Catholics and Protestants. The text was finished on June 28, 2018, and never previously published.

Chapter 5

Entitled “Topics of moral theology,” this chapter is dedicated to moral issues. It consists of the essay “'The Church and the scandal of sexual abuse,” first published in 2019 in Klerusblatt, a monthly journal for Bavarian clergy.

Chapter 6

Entitled “Occasional contributions,” this chapter brings together texts marking various anniversaries.

It opens with the text “The International Theological Communion,” an address delivered on Oct. 22, 2019, at Mater Ecclesiae Monastery to mark the commission’s 50th anniversary. It was published at the time on the body’s website under the heading “Papal addresses.”

Next is the essay “100 years since St. John Paul II’s birth,” written on May 4, 2020, ahead of the centenary of the Polish pope’s birth on May 18, 2020. An English translation of the text was released on May 15, 2020, by the Polish bishops’ conference.

This is followed by an address in honor of the 75th anniversary of the death of Fr. Alfred Delp, the German Jesuit executed by the Nazis on Feb. 2, 1945. Benedict wrote the text, entitled “75 years since the death of Jesuit Fr. Alfred Delp,” on Oct. 15, 2019. This is the first time it has been published in Italian.

The book’s final text is an interview about his patron saint, St. Joseph, called “His silence is also his message.” The interview was given to Regina Einig and published in the German newspaper Die Tagespost on April 1, 2021, marking the Year of St. Joseph. The text has not appeared in Italian before. Benedict says that the interview reflected his understanding, which became clearer as he aged, that St. Joseph’s silence speaks to us and guides us toward wisdom.

“Che cos’è il Cristianesimo” (“What is Christianity”), by Benedict XVI, is published in Italian by Mondadori.  It will be published in English by Ignatius Press; a date of publication has not yet been announced.


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