Monsignor Kevin Irwin , Walter J. Schmitz Chair of Liturgical Studies, was quoted in an Atlantic article in advance of Laudato Si , the pope's encyclical on the environment. He was again quoted after the encyclical was released. See below.
From: Atlantic Date: June 15, 2015 Author: Emma Green
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The Vatican has reacted so strongly to the leak because this encyclical is a very big deal within the Catholic world. It's one of the most formal statements the pope can make about Catholic doctrine, and it's the first of his papacy. (Last spring, he released another piece of writing on the topic of poverty, but it was a slightly less formal document called an apostolic exhortation.) Francis chose a theme that's long been a focus for pontiffs: Benedict XVI is cited 21 times in the draft version of the text, and John Paul II is cited 22 times. But this is the first instance in which the environment has been a topic of an encyclical. "No pope has ever issued a statement [about the environment] on this level of document," said Kevin Irwin, a priest and theologian who teaches at the Catholic University of America. "John Paul put it into a World Day of Peace message, but a World Day of Peace message is down the rung on the ladder of the hierarchy of Catholic documents. And Benedict gave a number of homilies and speeches on it, but never a document on this level."
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Read more about Monsignor Irwin's expertise .