The Tradition of thought in the Roman Catholic Church is broad and expansive -- even somewhat elastic and at times subtle and nuanced. Nevertheless, the basic rule is that professional theologians are supposed to publish only thoughts that are demonstrably within the box of the Tradition, not out of the box.
By definition, the bishops are the official church authorities who adjudicate what is in and what is not in the box of the Tradition. Naturally many lay Catholics volunteer to serve on the neighborhood watch to assist the bishops in carrying out their jobs as the official thought police. Because the mythology of the church says that the church was founded by the Word of God (also known as the Second Person of the divine trinity), thought crimes should be avoided -- and anathematized officially by the thought police (the bishops) when they are detected.
Of course the political-correctness police in American culture today also function as thought police and anathematize politically incorrect thought crimes. As long as we have in-groups and out-groups, we will probably also have thought police to patrol the borders.
In any event, Friedrich Nietzsche selected Zarathustra (also known as Zoroaster), the founder of the Zoroastrian religion, as the key influence on the Christian tradition of thought about the devil -- and about good and evil as bipolar opposites. In the Christian imagination, the devil has had a long and colorful history.
UNDERSTANDING ROMAN CATHOLIC TRADITION
Now, in the book Jung's Seminar on Nietzsche's Zarathustra: Abridged Edition (1998), C. G. Jung offers one way for us to understand the Roman Catholic fixation on Tradition, even though he does not explicitly advert to this Tradition of thought:
"[T]he psychological justification for such an attribute [such as the uncritical veneration of Tradition in properly indoctrinated Roman Catholics, including the bishops and popes] is that the condition in which such people live is a godlikeness. If you assume that there is a metaphysical god [as properly indoctrinated Roman Catholics do] and that people live a metaphysical existence, then they are like God; and psychologically the metaphysical place would be the unconscious. People who live in the unconscious [e.g., properly indoctrinated Roman Catholics] are like the unconscious; they are also unconscious. So, in so far as you can call the reality of the unconscious the deity, they are like the deity: they are like unto God. This shows itself in reality through the fact that they have self-evidence in life, they feel justified [because St. Paul says that Christians are justified by their faith in the mythic Christ]; it is certain that their way is right -- or wrong. There is no doubt about it" (page 98).