“The faithful are bound to profess their faith publicly, whenever silence, subterfuge, or their manner of acting would otherwise entail an implicit denial of their faith, a contempt of religion, an insult to God, or scandal to their neighbor. Any baptized person who, while retaining the name of Christian, obstinately denies or doubts any of the truths proposed for belief by the divine and Catholic faith, is a heretic; if he abandons the Christian faith entirely, he is called an apostate; if, finally, he refuses to be subject to the Supreme Pontiff, or to have communion with the members of the Church subject to the Pope, he is a schismatic.” Canon 1325, paragraph 1.
Note well that we are bound to profess our Faith publicly. Further we are bound to educate ourselves in the basic teachings of the Catholic Faith to the level of the Catechism of the Council of Trent. Our Pastors are obliged to teach us from that catechism, which is why the Council of Trent ordered it prepared.
Pope Saint Pius X ordered Pastors to set aside time each Sunday for the teaching of catechism to all of their flock, adults as well as children in the Encyclical, Acerbo Nimis. Then he states: “In this matter, they are to use the Catechism of the Council of Trent, in such a way as to cover in four or five years all the matter relating to the Creed, the Sacraments, the Ten Commandments, Prayer and the Commandments of the Church, and also the matter on the evangelical counsels, grace, the virtues, sin and the four last things.”
The Catholic Encyclopedia reports: “Other synods, and the Fourth Lateran Council (1215) under Pope Innocent III, repeated and enforced this decree, especially the Synod of Toulouse (1229), which established inquisitors in every parish (one priest and two laymen). Everyone was bound to denounce heretics, the names of the witnesses were kept secret; after 1243, when Innocent IV sanctioned the laws of Emperor Frederick II and of Louis IX against heretics, torture was applied in trials; the guilty persons were delivered up to the civil authorities and actually burnt at the stake.”
Saint Thomas Aquinas writes: “In cases of necessity where faith is in danger, every one is bound to proclaim his faith to others, either to give good example and encouragement to the rest of the faithful, or to check the attacks of unbelievers: but at other times it is not the duty of all the faithful to instruct others in the faith.” (II-II Q3 A2 reply 1)
Practical Application
What do we do, when it is our own Pastor, who had doubted or denied the Faith and is subverting us with his teaching? We appeal to our Bishop. What do we do, when it is our Bishop? We appeal to the Pope. What do we do, when it is our Pope? There is no precedent in history to guide us, but we do have the general teaching of the Church, which we are considering.