The word “heretic” is relative to one’ point of view, first of all.
you probably mean, when is one in heresy against the Catholic Church? You are in heresy when you reject anything that the Catholic Church teaches.
There’s no measuring stick to decide this. There are no heresy cops. When you reject the teaching, then you are a heretic from the Catholic faith.
This is not to say that you have to believe everything that any individual in the Church might tell you. They may be confused or misunderstand or perhaps not express the teaching correctly, so this is probably outside the scope of your question.
The odd category, as far as I’m concerned, has to do with something related to what I said in the previous paragraph, and that is, private revelations.
I’m not an expert or an academic, but I think this is a fuzzy subject, with vague boundaries. The Church’s position is that a Catholic is not bound in faith to private revelations, even very well-known ones. So, as I understand it, you do not have to believe that the Virgin Mary appeared to Juan Diego. You will offend many people if you express your doubts or skepticism about this, but you do not have to believe it. Same goes with the apparitions at Fatima or at Lourdes.
The Church says that private revelations are primarily for THE PERSON WHO RECEIVES THEM. The most recent example is that of Sister Faustina Kowalska, generally referrred to as “The” Divine Mercy. I’m not going to say anything more about it, except this. I am bothered by people who want to transform PRIVATE revelations into PUBLIC revelations. The Church says that Public revelation ended with the death of the last apostle.
So, the assertion that Sister Fausina had visions of Jesus Christ with new messages for humanity falls on my deaf ears. It is offensive to my faith. Now, that’s just me speaking.
Other people are awed about Sister Faustina, etc.
I wrote to a priest on the EWTN Catholic cable network, and I challenged him about his preaching at Mass about private revelations which we do not have to believe in. He kindly replied that the Church has “approved” talking about certain things and that is what he was preaching about, what has been approved.
The issue here spirals down to what has the Church “approved” and why had it done that. I can accept it on the general sense of the Church holding up the lives of saintly people for our study and imitation. I can accept that, I suppose, up to a point.
Another general approach to this question has to do with the idea of dogmas versus doctrines. Dogmas are the teachings of the church defined as those which we “have to” believe,if you want to put it in those simplistic terms.
Doctrines, on the other hand, are also teachings of the Church but the Church has modified doctrines in the past. The last Pope issued some guidelines that would suppress the idea of “Limbo” – the edge of heaven, where it was thought that babies who were born but not baptized dwelled after their premature death. The purpose of the earlier teaching had been to give some comfort to parents who lost children in childbirth or shortly thereafter, but before they could be baptized into the Church. The Church now emphasizes the sovereignty of God in determining the post-life disposition of the souls of these infants.
A couple decades ago, the Church retracted the listing of certain saints, due to a lack of adequate records about them. So, the popular devotion to St. Christopher, the patron of travelers, was suppressed.
If you were to read and read and read on this subject, you would find that the Church emphasizes its role in expressing the gospel in modern terms, which might be seen as changing things from the past. But, it is held that is not the case. The Church is viewed by itself as being “constant.”
I read a pithy remark yesterday that may also illumine this subject. It was something to the effect that you should be careful not to limit your belief and practice to just what YOU accept, because then it is NOT what God teaches. You cannot cherry-pick the things you like and reject the rest.
IF the authentic teaching of the Church bothers you in some way, then it is up to YOU to develop your interior spiritual life in accordance with the Church. It may take a long time, but you are to submit to the Church’s teaching, even if it is not all understandable to you.
