In an excerpt of a new book released on Saturday in Italy, Pope Francis made the church’s stance on gay priests clear: they should not, in his opinion, be accepted into the Catholic clergy. “In our societies, it even seems that homosexuality is fashionable and that mentality, in some way, also influences the life of the church,” the Pope said in The Strength of a Vocation, according to The Guardian. The Strength of Vocation is by Father Fernando Prado and based upon hours of interviews Prado did with the pontiff about the challenges facing clergy members. The book is set to be released in full on Monday in 10 languages, the BBC reported. During one interview in particular, the Pope said homosexuality among clergy members was a concern for him. “The issue of homosexuality is a very serious issue that must be adequately discerned from the beginning with the candidates,” Francis said of potential clergy members, according to The Guardian. “This is something I am concerned about, because perhaps at one time it did not receive much attention.