In July 2007, Pope Benedict XVI issued "Summorum Pontificum," designating two uses" or "forms" of the Roman Rite, declaring the Missal of Paul VI to be the "ordinary form" and the 1962 Missal of John XXIII to be its "extraordinary form." On the same day, the pope also published a letter to bishops, "Con Grande Fiducia," to accompany and offer commentary on this "motu proprio."
Johnston, William H.