Gospel faith means unknowing, not needing to know, allowing God and life to be mystery. But since the time of the early Middle Ages (at least), we have turned faith into its exact opposite: the need for certainty and an obsession with doctrinal answers. This reaches its most despicable point in religious fanaticism. We have been reflecting on the need to distinguish religious, specifically Christian, fanaticism from authentic, Gospel faith. The need to do grows by the day as elements in the Pentagon and in Evangelical circles label the war with Iran as a crusade.

One of the largest problems with fanatics is they believe their ideas about God, how people should behave, and the ordering of society are all divine. Their ideas are their idols, which they believe with zealous certainty. They make a critical error, however, and one which scripture warns us about. They think they can grasp God by their own thoughts, thinking, and mind. “For my thoughts are not your thoughts, nor are your ways my ways—oracle of the LORD. For as the heavens are higher than the earth, so are my ways higher than your ways, my thoughts higher than your thoughts” (Isaiah 55:8-9). Dwelling in the darkness of mystery, God is invisible and uncontrollable to the human ego. The fanatic does not like this; indeed, he hates it because he is not really interested in God but in control. The fanatic wants to control others and turn them into copies of himself.

Unfortunately, fanatics are found in the Catholic Church as much as any other religion. Fr. Mark Mass, SJ, wrote a book titled Catholic Fundamentalism in America, published in 2025. He describes Catholic fundamentalism as a “reactive, militant, sectarian, ‘fundamentalist’ movement emerged within American Catholicism in the decades after World War II” (Massa, 8). Catholic fanaticism appears in various groups that share a few characteristics: ideology over faith and reality, sectarianism over communion, militancy and sometimes violent tendencies, and narcissism.

Catholic fanaticism centers on ideology, some set of ideas, as ultimately important. Fr. Massa brings up the Society of St. Pius X (SSPX) as an example. They reject the teachings of the Second Vatican Council. Notably, they reject the modern form of the Mass. They want it back in Latin and in the Tridentine form. SSPX’s founder, Archbishop Marcel Lefebvre, continually defied papal authority until Pope John Paul II excommunicated him and any in the society because Lefebvre ordained four bishops without the consent of the Vatican. Lefebvre had a history of ordaining priests without the authority of the pope. SSPX had sown discord in the church by its grim insistence on adhering to pre-Vatican teachings and the Tridentine Mass. The Vatican then lifted the excommunication in 2009.

With groups like SSPX, faith becomes strict adherence to a set of ideas, whether about the Mass, the human body, or the church. Faith, then, is not about surrendering to God but swallowing an ideology. Disagreement or doubt about the ideas, then, is the sin of unbelief. Fanatics think faith equals certainty, holding fast to one’s ideas against, especially, any compromise with the world. But real faith embraces the experience of doubt. Even worse, fanatics treat ideas as more important than people and reality. This can be a bridge to violence.

Further, Catholic fundamentalism and fanaticism display “a strong sectarian impulse…sectarianism…holds that the church is a community of true believers, a precinct of righteousness within and yet in opposition to the unredeemed world of sin, pronouncing judgment upon it and calling it to repentance, but never entering into dialogue with it” (Massa, 9). This directly counters the catholic nature of the church, our communion with God and each other, “saints with sinners, the pure with those considerably less pure, the converted with the not-quite converted…sectarianism is the polar opposite of the very word ‘catholic’…” (Massa, 10). It means drawing a strict line around one’s community of insider believers – who hold the fanatic’s peculiar beliefs – as making up the real church opposing the false church. This implies a very large group of outsiders.

Massa describes how Catholic fundamentalists talk about fellow Catholics they believe are betraying the faith as well as despised groups such as the LQBTQ+ community, feminists, or atheists: “the almost breathless, accusatory, militant tone of their denunciations of others, especially fellow Catholics.

There would not be—there could not be—any question of compromise or respectful conversation with those who disagreed” (Mass, 15). This revulsion towards compromise fuels a rage that foments the tendency to violence, at least violent rhetoric.

Catholic and all religious fanaticism is inherently narcissistic: everyone has to believe, act, and have the same ideas as me. Fanaticism thoroughly rejects any difference. But Gospel faith can accept paradox, otherness, and the tension within oneself of being both sinner and saint. Fanatics are terrified of their own humanity, weakness, poverty, and sin. They need rigid structures and beliefs to keep them and others pure according to their impossible moral standards. Gospel faith accepts the inner poverty of the human person. We find such faith in St. Therese of Lisieux: “Yes, it suffices to humble oneself, to bear with one’s imperfections. That is real sanctity.”

Fanaticism has an exaggerated focus on the self. Gospel faith calls for the loss of self as focus and center of life. St. Therese writes, “One has only to love Him, without looking at one’s self, without examining one’s faults too much” We have only to pray, to turn our soul’s gaze to God alone, not to a pet ideology or a compulsive focus on a morality. This does not please God! Love does! St. Therese tells us the same: “What really pleases Jesus is that He sees me loving my littleness and my poverty, the blind hope that I have in His mercy…This is my only treasure…why would this treasure not be yours?”