The only valid substance for a consecrated host is unleavened bread made from gluten—unfortunately for some, a highly allergenic substance. So why can’t the Church use rice bread for the Eucharist? Scripture offers several answers, but the argument boils down to this: The matter we use for sacraments is, quite literally, significant.
We live in an age of diversity, say the arbiters of the cultural zeitgeist. Many Catholics are only too familiar with the concept, so much so that we sometimes wish our fellow Catholics—the ones with the wrong approach to liturgy or moral teaching or social justice—would just go away. But catholic means "here comes everybody." The Church is a refuge for all sinners, beginning with ourselves.
Controversy continues to swirl around the pending beatification of the much-maligned Pope Pius XII. In debating whether Pius did or did not do enough to protect the Jews from Hitler, it is instructive to remember that one influential religious leader actively promoted their slaughter. He was a Muslim cleric: the Grand Mufti of Jerusalem.
Did the Second Vatican Council’s Decree on Ecumenism change the centuries-old Tradition that the only path to salvation is through the Church? No: A close comparison of Vatican II’s decree with Pius XI’s On Religious Unity reveals a shift in discipline, not doctrine. What Pius and the Council both condemned is a false concept of ecumenism.
"Between heresy and schism there is this difference, that heresy perverts dogma, while schism, by rebellion against the bishop, separates from the Church. Nevertheless there is no schism which does not trump up a heresy to justify its departure from the Church."
~ St. Jerome, (In Ep. ad Tit., iii, 10), remarking on how practically and historically, heresy and schism nearly always go hand in hand.