The faithful who are interested in the musings of Pope Benedict XVI will soon have the opportunity to buy a collection of his essays.

Selected writings by Pope Benedict, who passed away Dec. 31, will be available in book form this week.

The title of the book is “What is Christianity?” according to Italy 24 News. It will be available for purchase on Friday. The book contains an essay on themes of Christianity, as well as other unpublished essays Pope Benedict wrote throughout his life. 

“Pope Benedict XVI is publishing a book posthumously,” Nick Chancey, campus minister and director of the Marshall Catholic Newman Center at Marshall University in West Virginia, said in a Jan. 10 tweet. 

The book’s essays represent some of the key foundations of Pope Benedict's philosophy. Christianity's history, religious communications, and relationships between Christians and Jews are among the topics the essays are about, Mondadori Books says in its description of the collection. Some of the themes are more personal to Pope Benedict, touching on his deep love of nature, as well as his native country, Germany.

Pope Benedict XVI was born Joseph Aloisius Ratzinger in 1927. Catholic News Agency reports that he has produced more than 1,300 essays, articles and other scholarly works, more than 60 books, three encyclicals and four apostolic exhortations over the course of his life. They come in the form of theological works, in-depth spiritual thoughts, popular books and more.