"Do not allow yourselves to be deceived by the cunning statements of those who persistently claim to wish to be with the Church, to love the Church, to fight so that people do not leave Her...But judge them by their works. If they despise the shepherds of the Church and even the Pope, if they attempt all means of evading their authority in order to elude their directives and judgments..., then about which Church do these men mean to speak? Certainly not about that established on the foundations of the apostles and prophets, with Christ Jesus Himself as the cornerstone (Eph. 2:20)." [Pope St. Pius X (c. May 10, 1909)]These brilliant and illuminating words of St. Pius X serve as a warning, of course, not only against those on the lunatic self-styled "traditionalist" fringe who protest their fidelity to the Catholic Church even while they undermine the confidence of the faithful in the authority of Rome, but also--and often more pointedly these days--against those on the lunatic self-styled "progressivist" fringe, who, I fear, are ever becoming more mainstream, protesting their fidelity to the Catholic Church even while they undermine the confidence of the faithful in the authenticity of traditional Church teaching, the reliability and credibility of the Bible, and the importance of the Sacraments of the Church. See, for example, my review of a magazine that has been sometimes aptly (mis-) titled "U.S. Protestant," "U.S. Heretic," or "U.S. Dissident"--namely, U.S. Catholic ("What I Learned from U.S. Catholic," originally published in This Rock magazine).
For more on modernist and traditionalist dissent and confusion, click here.