Today, division and schism are officially acknowledged to exist not only outside of but within the Church. Her unity is not only threatened but already tragically compromised. Errors against the Faith are not so much insinuated but rather an inevitable consequence of liturgical abuses and aberrations which have been given equal recognition.
To abandon a liturgical tradition which for four centuries was both the sign and the pledge of unity of worship (and to replace it with another which cannot but be a sign of division by virtue of the countless liberties implicitly authorized, and which teems with insinuations or manifest errors against the integrity of the Catholic religion) is, we feel in conscience bound to proclaim, an incalculable error. Short Critical Study on the New Order of Mass.