We must also be wary of those who publish the Bible with new interpretations contrary to the Church’s laws. They skillfully distort the meaning by their own interpretation. They print the Bibles in the vernacular and, absorbing an incredible expense, offer them free even to the uneducated. Furthermore, the Bibles are rarely without perverse little inserts to insure that the reader imbibes their lethal poison instead of the saving water of salvation. Long ago the Apostolic See warned about this serious hazard to the faith and drew up a list of the authors of these pernicious notions. The rules of this Index were published by the Council of Trent; the ordinance required that translations of the Bible into the vernacular not be permitted without the approval of the Apostolic See and further required that they be published with commentaries from the Fathers. The sacred Synod of Trent had decreed in order to restrain impudent characters, that no one, relying on his own prudence in matters of faith and of conduct which concerns Christian doctrine, might twist the sacred Scriptures to his own opinion, or to an opinion contrary to that of the Church or the popes. Though such machinations against the Catholic faith had been assailed long ago by these canonical proscriptions, Our recent predecessors made a special effort to check these spreading evils. With these arms may you too strive to fight the battles of the Lord which endanger the sacred teachings, lest this deadly virus spread in your flock.

-Pope Pius VIII

Traditi Humilitati, May 24, 1829