This page answers some of the most common questions about the difference between Roman Catholicism and Orthodox Christianity.

What is necessary for Christian Unity between Rome and the Orthodox Churches?

It’s simple – the Pope must confess the Orthodox faith, completely, with no reservations. For a detailed view by one Orthodox theologian on the necessary conditions, please see the article Roman Presidency and Reunion in Our Time by Fr. Thomas Hopko.

Do Orthodox Christians pray the Rosary?

The Rosary dates from the 1400’s, well after the split between East and West, so the use of the Rosary is unknown in the East. In Orthodoxy there is, however, the practice of praying the Jesus Prayer – “O Lord, Jesus Christ, Son of God, have mercy upon me, a sinner” – on a set of prayer beads. But only this single prayer is associated with the beads, and there is no notion of decades or of meditation upon specific Mysteries while using the prayer beads. So using the prayer beads is a much simpler devotion in practice than praying the Rosary.

What about Purgatory?

Purgatory was developed in the West to explain how the dead can work off the residual “debt” due to sin prior to the Second Coming. The assumption is that the slate needs to be clean before a person can come before the judgement seat. The Orthodox view of salvation is more process-oriented, and does not assume that sin and grace are quantifiable “substances” that must somehow be in balance before someone can enter God’s Kingdom. There is just sin, and although some are more serious than others, Orthodox do not make the distinction between mortal and venial sins that Roman Catholics do. All sin is believed to be serious in Orthodoxy. We work toward holiness (deification or theosis), and this is a process that will not be completed in this lifetime. Indeed, the work of holiness is an eternal one, since God’s holiness is limitless and hence forever beyond us! So we are in the middle of the process of sanctification at the moment of our deaths. How do we know we are ready? It is our jobs to make sure we are prepared for our deaths, and to make sure that we have spent a life working toward holiness. As a consequence of these differences, the doctrine of Purgatory is considered unnecessary in Orthodoxy.

Orthodox and Catholics both believe in the real presence of Christ in the Eucharist. So does Orthodoxy believe in transubstantiation?

We believe in the real presence and accept it at face value, as a mystery. Western theology tends to approach theological matters via the use of reason; this is a legacy of Augustinianism and the medieval Scholastics, who applied the techniques of Greek philosophy to the investigation of theological matters. Orthodoxy believes that certain matters are beyond the use of reason, so it is presumptuous for us as limited human beings to think that we can use our reason to understand that which is beyond us. As a consequence, we Orthodox are comfortable with accepting mysteries like the Real Presence as what they are – mysteries, without feeling obliged to explain them.

Can you explain the Orthodox view of Original Sin?

The Western doctrine of Original Sin, formulated originally by Blessed Augustine, presumes that we inherit Adam’s guilt. This is the consequence of a mistranslation in St. Jerome’s Latin Vulgate of Romans 5, which is the version of the New Testament that Augustine used in formulating his doctrine. Orthodox believe that we inherit Adam’s mortality, not Adam’s guilt.

Why don’t Orthodox believe in the Immaculate Conception?

Mary (like all of us) was born mortal as a result of the Fall, but without Adam’s guilt. But for Roman Catholics, a “special” birth for Mary was necessary so that Christ could be born to a spotless vessel. So the Immaculate Conception is a natural consequence of the Augustinian doctrine of Original Sin in the West, but is not needed in Orthodoxy to explain how mortal Mary could have given birth to her All-Holy Son.

What are the differences in belief regarding the Assumption of Mary?

Roman Catholics believe that Mary, because she was born without the stain of Original Sin (see previous question on the Immaculate Conception), did not have to die; as a consequence, she is the only human being to be assumed directly to heaven without passing through death. On the other hand, Orthodox believe that Mary inherited Adam’s mortality like all other human beings, and therefore died like the rest of us. However, her Son (the new Adam) immediately raised her from the dead as one of the first fruits of his Redemption, and she was then assumed into heaven. This is why the icon of Mary’s death (her “Dormition” shows her lying on her death bed, with her Son behind her holding a baby in swaddling clothes. The baby represents His mother who he has raised to her new life with Him in heaven. Each August, we Orthodox celebrate Mary’s Dormition (falling asleep) rather than her Assumption.

What does `Theotokos’ mean?

Mother of God, or literally “God-bearer.” The title was given to Mary at the Third Ecumenical Council in Ephesus, in 431, to affirm that in the Incarnation God was truly born of a mortal woman. It’s a title that Roman Catholics as well as Orthodox can proclaim!

Why are Orthodox priests allowed to marry?

Technically speaking, we ordain married men – neither priests nor deacons may marry once they are ordained (in some traditions, this applies to ordination of Subdeacons as well). The decision to marry or not must be made prior to ordination, and in the event of the death of his wife, an ordained clergyman may not remarry.

Specifically, It was at the First Lateran Council in 1123 that celibacy became mandatory for Roman Catholic priests. A local council in the West in Elvira, Spain in 316 declared that celibacy was mandatory for clergy, and the practice began to spread in the West over the following centuries under the encouragement of various Popes. Orthodox have always insisted that celibacy had traditionally been optional for clergy since the first century, citing scriptural and other evidence for married priests and bishops (see for example Mark 1:30, Timothy 3:1-5). And the decisions of local councils are not binding on the church as a whole; only the decisions of ecumenical councils, when accepted by the community as a whole, are binding. Note that as is the case in the West, bishops have been celibate in Orthodoxy since the fifth century, a canon law instituted to halt the loss of land holdings to the descendents of married bishops. Note, too, that all monastics are celibate in the Orthodox Church. Also, celibacy has always been understood as a tradition rather than as unchangeable doctrine in the West, which is why there have been exceptions made to Roman Catholic priestly celibacy, especially in recent years. There are no doctrinal reasons why a married priesthood could not be restored in the West.

Both Orthodox Christians and Roman Catholics make the Sign of the Cross, but why is the order different (Orthodox right shoulder first, RCs left shoulder)?

The sign of the cross is a tradition dating back to the second century and it was made from the right to left shoulder in both the West and East until the sixteenth century. For example, Pope Innocent III issued an instruction around the year 1200, recommending the right to left order (though he was aware of the other tradition). In the sixteenth century, Pope Pius V changed the tradition for Roman Catholics to further distinguish the Western church from the Orthodox Church.

Roman Catholics make the sign of the cross with the five fingers next to each other, to represent the five wounds of Christ (head, hand, hand, torso, feet). Orthodox make the sign of the cross with the thumb, index, and middle fingers together, representing the Trinity, and the fourth and fifth fingers pressed into the palm to represent the two natures of Christ.

Why are Orthodox children allowed to partake in Communion, but Catholic children have to wait until 1st or 2nd grade?

Roman Catholic doctrine holds that a child must be old enough to intellectually understand the mystery of Christ according to “his capacity.” They should be able to discern the difference between the eucharist and ordinary bread. Western doctrine places a premium on the role of reason in understanding God and in forming a relationship with Him. Orthodoxy, on the other hand, believes that God in His Essence is unknowable, and dwells in “divine darkness.” No one will ever apprehend the mysteries of God, the Incarnation, or the Eucharist through reason. Why, then, withhold the grace of the sacrament from those whose understanding is after all only a little less than an adult’s? As a consequence, Orthodox do not believe in holding back children (or those who who are developmentally challenged and are incapable of reason) from receiving the Body and Blood of Christ.

Why doesn’t the Orthodox Church celebrate Augustine of Hippo as a Saint?

There is some difference in practice in the Orthodox Church regarding this. In general, Augustine of Hippo is not called “Saint Augustine,” but is often called “Blessed Augustine.” Depending on which Orthodox author you read, you may find Augustine called simply Augustine, Blessed Augustine, or even Saint Augustine. Because some of Augustine’s writings are in conflict with the teachings of Orthodoxy and because they have been misused by the Western “Augustinians” who followed him, he is viewed with some caution in the East as a Father of the Church. His writings are thought by many in the East to be the root cause of the divergence of Western theology from the Orthodox understanding of God and Original Sin, and ultimately of the schism of the Western Church.

This excellent question also raises the issue of sainthood. In the West, the declaration of a Saint is a more-or- less top-down process; by recognition of miracles by the hierarchy, analysis of the prospective Saint’s life under the direction of the hierarchy; and the juridical approach involving a “Devil’s Advocate.” In the East, a Saint is recognized as such by more of a bottom-up process: the community recognizes the Saint’s holiness, which is then acknowledged and proclaimed by the hierarchy. It is worthy of note that starting under Pope John Paul II, the Roman church has been following more of an Eastern model in recognizing and declaring Saints

Why does the Orthodox church use leavened bread and the Roman Catholic church use unleavened bread (wafers)?

The differences between East and West on the use of bread in the Eucharist arose because of differences in understanding of the nature of the Last Supper (as a fellowship meal per the Gospel of John in the East, as a Passover meal per the synoptic gospels in the West), and perhaps also of the theological symbolism of leaven. The issue of leaven is one of the issues leading to the split between East and West, with the West coming to insist by the eleventh century that the East’s use of leavened bread is a “heresy.”

Why do Orthodox Christians say that the Holy Spirit proceeds only from the Father, rather than from the Father and the Son?

Because that is the formulation in the Nicene Creed, which represents the faith passed down from the apostles. It agrees with the theology of scripture; the Gospel of John very clearly says “But when the Helper comes, whom I shall send to you from the Father, the Spirit of truth who proceeds from the Father, He will testify of me.” (John 15:26). The filioque clause was introduced in the West at a local council in Toledo, Spain in 589. Over the coming centuries, it would spread in the West as theology (under the influence of Charlemagne’s Frankish theologians) drifted from a common understanding with the East. In the year 1274, a council of the Roman Catholic church in Lyons, France made the filioque an official part of the Nicene Creed in the West.

How do Orthodox Christians view the authority of the Pope, and the Primacy of Peter?

The Patriarch of Rome is one of the five historic patriarchates of the Church, the others being Constantinople, Antioch, Jerusalem, and Alexandria. Orthodox accorded the Pope of Rome the respect due the first among equals prior to the split in 1054; we would agree that there is a Primacy accorded the Pope of Rome. However, we hold that historically this Primacy was always understood as a Primacy of honor rather than a Primacy of authority. Western theologians would counter that the understanding of the special status of Papacy “evolved” over time in the West under the influence of the Holy Spirit; Orthodoxy would insist that the authority granted the first bishops, the apostles, was granted once and for all, and that the revelation of authority in them within the Body of Christ did not and does not “evolve” over time.

Why did the Orthodox Church split off from the Roman Catholic Church?

It’s a matter of how you interpret the events of history, isn’t it? From an Orthodox perspective, it’s the West that left the One, Holy, Catholic and Apostolic Orthodox Church over a period of theological drift that spanned centuries. From a Western perspective, it’s Orthodoxy that went into schism by refusing to acknowledge the West’s growing perception of the absolute authority of the Papacy. We pray for a healing of this rift, and a restoration of the Patriarchate of Rome to its role as first among equals in the One True Church. See the excellent article listed in the answer to the question on Christian Unity.