On July 16, 2021, the Vatican issued a motu proprio on the Latin Mass under the title of Traditionis Custodes which effectively revoked Pope Benedict’s motu proprio Summorum Pontificium, which made the Latin Mass more readily available to the faithful. That story began in 1988 when Pope John Paul II issued his own motu proprio Ecclesia Dei in the wake of the Lefebvrite schism of that same year. Worried that the Lefebvrites would follow the Latin Mass out of the Church, Pope John Paul II made the Tridentine rite available on a limited basis. As part of his efforts to end the Lefebvrite schism, Pope Benedict XVI lifted the excommunications of the four bishops Archbishop Lefebvre consecrated and expanded access to the Tridentine rite, by issuing his own motu proprio. Both Summorum Potificium and Ecclesia Dei were, in Pope Francis’s words, “motivated by the desire to foster the healing of the schism with the movement of Mons. Lefebvre. With the ecclesial intention of restoring the unity of the Church, the Bishops were thus asked to accept with generosity the ‘just aspirations’ of the faithful who requested the use of that Missal.”1