"Let all everywhere adopt and observe what has been handed down by the Holy Roman Church, the Mother and Teacher of the other churches, and let Masses not be sung or read according to any other formula than that of this Missal published by Us. This ordinance applies henceforth, now, and forever, throughout all the provinces of the Christian world ... Would anyone, however, presume to [alter … More

"Let all everywhere adopt and observe what has been handed down by the Holy Roman Church, the Mother and Teacher of the other churches, and let Masses not be sung or read according to any other formula than that of this Missal published by Us. This ordinance applies henceforth, now, and forever, throughout all the provinces of the Christian world ... Would anyone, however, presume to [alter it], he should know that he will incur the wrath of Almighty God and of the Blessed Apostles Peter and Paul. "

Pope Pius V, Quo Primum, 1570