In a new book, Pope Francis called for an investigation into whether Israel’s ground offensive in Gaza constitutes a genocide, sparking intense debate about the war — and also raising questions about the tangible impact that papal statements have on Catholics and global politics.

Pope Francis has said that allegations of a genocide in Gaza should be “carefully investigated” marking some of his strongest criticism yet of Israel’s war with Hamas.

While Pope Francis has criticized the war before, this is the first time he has publicly suggested an investigation, according to excerpts from a new book.