Infallible vs. Non-infallible vs. Fallible
Many Catholics have fallen into a type of fundamentalism, in which they over-simplify the Faith. They don’t accept any type of theological argument or theological opinion (except their own). They consider all teachings of the Magisterium to be infallible — or if they distinguish between infallible and non-infallible teachings, they don’t see any practical difference. However, they have misunderstood many doctrines, have confused their own theological opinions with doctrine, and do not accept correction.
One solution to this problem is for the faithful to make clear distinctions between infallible teachings of the Magisterium, non-infallible teachings of the Magisterium, and fallible theological opinion. This distinction is always useful, but it will become essential during the great apostasy.
The Church will see one short-lived papacy after another. One pope will be liberal, and the next conservative, and the third will have yet a different point of view. But each Pope will be a valid successor of Peter and the true Vicar of Christ. Successive Popes will disagree in their non-infallible teachings, as well as in their personal theological opinions. The faithful must not accuse any Pope of heresy, even when the non-infallible teachings of successive Popes do not agree. For heresy is not found in disagreeing with a non-infallible teaching, nor is it found in erring on a matter of opinion (on an open theological question) pertaining to the Faith.
The Pope can never fall into heresy, and his infallible teachings cannot err. But some degree of error is possible in his non-infallible teachings. Why should we give the religious submission of will and intellect to non-infallible teachings when those teachings might err? First, the error can never reach to such an extent as to lead us away from the path of salvation. Second, as a set, the non-infallible teachings of the Church contain few errors. Third, the set of non-infallible teachings are important to the path of salvation. You cannot live the Faith based solely on infallible teachings.
But since non-infallible teachings can err, the faithful Catholic Christian, who believes in all the infallible teachings and in the vast majority of non-infallible teachings, can sometimes licitly dissent from a particular non-infallible teaching, if there is a sound basis in Tradition, Scripture, Magisterium. This truth, that some theological dissent from non-infallible magisterial teachings is licit, is actually a teaching of the non-infallible Magisterium (Human Life in Our Day). So whoever says otherwise contradicts himself. For he dissents from a non-infallible teaching, by claiming that dissent from non-infallible teachings is not licit.
As for fallible theological opinions, the faithful must not abandon theology. This approach has become popular in recent decades. On both the right and the left, many of the faithful no longer have any use for theological arguments. They believe whatever they wish to believe. They ridicule and summarily dismiss anything to the contrary. Their own theological opinions are baseless, and yet treated as if there were dogma. And all contrary theological opinions are considered useless. — Many souls are being harmed by this attitude.
“Other modes of latent fideism appear in the scant consideration accorded to speculative theology, and in disdain for the classical philosophy from which the terms of both the understanding of faith and the actual formulation of dogma have been drawn. My revered Predecessor Pope Pius XII warned against such neglect of the philosophical tradition and against abandonment of the traditional terminology.” (Pope John Paul II, Faith and Reason, n. 55.)
It is important to maintain a distinction between the infallible and non-infallible doctrines versus fallible theological opinions, from those of the Saints, to those of the Popes, to your own mere opinions. But it is just as important to give value to each fallible opinion, based on the weight of its theological argument. You cannot live the Faith based solely on doctrine. For there will be many occasions, especially in matters of morality, when you will need to make a pious judgment as to how Church teaching is to be interpreted and applied. And in considering matters of faith and salvation, there will be questions not answered by the Magisterium that you will need to answer, at least tentatively, in order to understand the interrelation of all the doctrines to one another and to a life lived in Faith.
If you wish to keep faith during the great apostasy, learn to distinguish between infallible doctrine, non-infallible doctrine, and theological opinion, and give each its due weight and consideration.