(Pope Leo XIII, Satis Cognitum, 1896, Paragraph IX – Taken from American Ecclesiastical Review)
My friends, does Pope Leo XIII in the quote above teach that it is the judgment of the Church that cuts off the heretic from the Church? No. As I have repeated over and over again, the public sin of manifest formal heresy per se (i.e., by its very nature) separates the heretic from the Church. In other words, one who knowingly, consciously, and willingly publicly asserts a proposition that is in direct contradiction to a Church teaching that must be believed with Divine and Catholic Faith separates himself from the Church by that very fact. This is precisely what Pope Leo XIII teaches us. This also precisely what Pope Pius XII teaches us (see here). Why is it, then, that so many in the so-called Resistance oppose the Magisterium by asserting that it is the judgment of the Church that separates from the heretic from the Church or that we must wait for the Church to judge when it is factually evident that another is a public manifest formal heretic? A fact is perceived by the senses and apprehended by the intellect. Our Lord gave us these faculties to use for His glory and the salvation of our souls. Many in the so-called Resistance have no problem using these faculties in judging that Vatican II and the Novus Ordo Rite of Mass are not Catholic even though the Church has not yet officially condemned them as such. Yet when it comes to using these same faculties to accept the above principle and/or apply it to judge a manifest heretic as such, they become paralyzed.
Note also that Pope Leo XIII teaches us that it is the unanimous teaching of the Fathers that one who recedes from the authoritative Magisterium in the least degree is outside of Catholic communion (see also here). Pope Leo XIII implies here that this teaching is infallible because a teaching unanimously held by the Church Fathers cannot be erroneous.
Finally, but not exhaustively, the teaching of Pope Leo XIII is evident in Canon 188.4º of the 1917 Code of Canon Law (and Canon 194 §1.2º of the 1983 Code) regarding loss of office:
“Any office becomes vacant upon the fact and without any declaration by tacit resignation recognized by the law itself if a cleric: Publicly defects from the Catholic faith.”
So the same paralyzed adherents of the so-called Resistance not only oppose the teaching of the Church and Fathers in their doctrine, they also oppose the Church in her Canon Law.
Wake up so-called Resistance; wake up.