Introduction

Have you ever wondered what the key differences are between Roman Catholicism and Eastern Orthodoxy? Both are Christian— ancient, apostolic, and sacramental. And both believe in the Holy Trinity. They share many core beliefs. But in 1054 AD, they split — in what’s known as The Great Schism. Why? Let’s break down the key differences.

Q & A: Key Differences
in belief and practice

1. Who leads the Church?

Catholics believe the Pope is the supreme head of the Church, infallible in doctrine.

Orthodox Christians honour the Pope as the Bishop of Rome, but reject his authority over all Christians. Instead, the Orthodox Church is led by several Patriarchs — bishops of important ancient dioceses (like Constantinople, Moscow, Serbia) — who share authority. Leadership is collective, and major decisions are made by councils of bishops.

2. What is the Filioque?

The Catholic Church added the phrase ‘and the Son’ to the Nicene Creed (a statement and prayer of core Christian beliefs), meaning the Holy Spirit comes from both the Father and the Son.

The Orthodox Church kept the original: the Holy Spirit proceeds from the Father alone.

3. What is Original Sin?

Catholics teach that we inherit guilt from Adam’s sin. Baptism washes it away.

Orthodox believe we inherit a fallen nature, not guilt. Baptism begins our healing and restores God’s image in us.

4. What is Salvation?

For Catholics, salvation is about justice — sin is guilt, punishment is deserved, and Jesus pays the debt.

For Orthodox, it’s about healing — sin is a sickness, not just a crime. Salvation is theosis, becoming more like God.

5. What happens in the Eucharist?

Catholics teach transubstantiation — the bread and wine become the body and blood of Christ in substance.

Orthodox call it a holy mystery. Christ is truly present, but they don’t define the mechanics.

6. Is there Purgatory?

Catholics believe in purgatory — a place of purification before heaven.

Orthodox reject purgatory but pray for the dead, trusting in God’s mercy and final judgment.

7. What is sin?

Catholics see sin as breaking divine law — guilt that must be confessed and punished.

Orthodox see sin as a sickness — it wounds the soul and needs healing. Sin offends God and creates distance between us and Him.

8. What about sex, marriage and divorce?

Both Catholics and Orthodox teach that sex belongs only within marriage.

Catholics teach that sex must always be open to life and see marriage as an unbreakable, lifelong union. Catholics forbid divorce. Annulments may be granted, but marriage is seen as indissoluble.

Orthodox allow pastoral guidance and discernment between spouses, and they accept divorce in certain cases. Remarriage is permitted, with repentance.

9. What about abortion?

Catholics condemn abortion completely (Catechism 2270–2275).

Orthodox believe life begins at conception but may show mercy in rare cases, especially to save the mother’s life.

10. Can clergy marry?

In the Catholic Church, priests take a vow of celibacy and do not marry.

In the Orthodox Church, parish priests can marry — but only before they are ordained as priests. Bishops are chosen from celibate monks.

How do they view each other?

11. How does the Orthodox Church view Roman Catholicism?

The Orthodox Church sees Roman Catholicism as a sister church that broke away after the Great Schism in 1054. It respects their bishops and sacraments but rejects some Catholic teachings. It does not see Catholicism as fully part of the true Church. Orthodoxy prays for unity without compromising its beliefs.

12. How does the Catholic Church view Orthodoxy?

The Catholic Church sees the Orthodox Church as a true Church with valid sacraments and apostolic succession but lacking full unity with the Pope. It respects Orthodoxy as a sister church deeply rooted in tradition and holiness. Though separated, Orthodox Christians are not considered heretical. The Catholic Church prays for unity and encourages ongoing dialogue for reunion.

13. How is Serbian Orthodoxy specifically different from Roman Catholicism?

All points above apply to the Serbian Orthodox Church. However, Serbian Orthodoxy blends faith and national identity— ’Srpstvo’ — more than other Orthodox branches. Especially true during periods of foreign rule (Ottoman, Austro-Hungarian).

For Serbs, the Church isn’t just a religious institution; it also protects the Serbian language, customs, saints, and historical memory. Saints like St. Sava, St. Nikolaj Velimirović are both spiritual and national icons.

Major feasts and Slavas (patron saint celebrations) are key parts of family and cultural life — blending tradition, ancestry, and faith.

Also, unlike Roman Catholicism, Serbian Orthodoxy (like the Russian Orthodox Church) follows the original Julian calendar, so holidays like Christmas, for example, fall on January 7th instead of December 25th.

In short:

Unlike Catholicism’s centralized leadership, Serbian Orthodoxy acts as both a spiritual and cultural foundation for Serbs in Serbia and abroad.

This makes the Serbian Orthodox Church not only a religious authority but also a cultural cornerstone for Serbs, both in Serbia and abroad.

Conclusion

Roman Catholicism and Serbian Orthodoxy have a lot in common. There are also differences in beliefs, leadership, and how faith and culture mix.

What else keeps us apart?

Undeniably, history and identity play a big role. Events like the Vatican’s support of Croatian Nazis in World War II has left deep wounds on the Serbian Soul. Any healing will take time.

In the meantime, hopefully, we’ve cleared up some of the nuances.

Think we missed something? Drop a comment or connect with your local Serbian Orthodox Church for more clarity.

It’s always there for you!

Serbian Orthodoxy vs Catholicism: Key differences.