Pope Leo claimed that the heavily criticized note Mater Populi Fidelis will be of ‘great benefit’ to the faithful and provides ‘important clarifications,’ despite it contradicting numerous popes and saints. “All this work will certainly be of great benefit to the spiritual growth of the holy and faithful People of God. Both Our Lady’s titles of “Co-Redemptrix” and “Mediatrix of all Graces” have been part of popular Catholic piety for hundreds of years. The late theologian Father Juniper B. Carol traced the use of “Co-Redemptrix” to a 14th-century liturgical book from Salzburg. Following the doctrinal note’s publication, several prominent Catholic priests, theologians, and Mariologists quickly came forward in defense of Our Lady’s titles.