Because priestly celibacy is a discipline, not a doctrine, and so there is room for diversity on the issue according to the customs of the respective rites. If celibacy were a doctrine, all rites would have to conform to the judgment of the Holy See on the matter because doctrines are true for everybody. But celibacy is a discipline (a practice that is legislated by proper ecclesial authority) that has been deemed to be spiritually beneficial. In the Latin rite, this spiritual discipline ordinarily is required of all men who seek priestly ordination. In the Eastern rites, it is practiced by the monks and by some secular priests, but it is not required of all men who seek ordination. Out of respect for the longstanding customs of the Eastern-rite churches, the Vatican allows the Eastern churches in communion with the Holy See to maintain their own properly constituted discipline on this issue.

There’s nothing wrong with changing rites if you so desire. It’s a bit of a hassle and really isn’t necessary. You can join an Eastern-rite parish without changing rites. However, if you still want to change rites, check with the pastor of the Eastern-rite parish you wish to join.

Let’s make some distinctions first: In the East, the liturgy that Roman Catholics call the Mass is called the divine liturgy. Some churches in the East are in union with the Catholic Church and others are not. Those that are in union with the Catholic Church are called Eastern Catholic; those that are not are ordinarily called Eastern Orthodox.

The Consecration of the Eucharist during the divine liturgy of both the Eastern Catholic churches and the Eastern Orthodox churches is valid. A Catholic of the Roman rite of the Church can attend an Eastern Catholic divine liturgy and receive Communion during that liturgy without problem, and the Eastern Catholic divine liturgy would fulfill the Sunday/holy day obligation. Although Catholics can occasionally attend Eastern Orthodox liturgies as a guest, those liturgies do not fulfill the Sunday/holy day obligation to attend Mass. Catholics ordinarily should not receive Communion at an Eastern Orthodox divine liturgy, though there are circumstances in which this is permitted.

If you have trouble discerning whether a particular Eastern church in your community is an Eastern Catholic or an Eastern Orthodox church, call your local diocese and ask.
—Michelle Arnold

Yes, the Holy See can appoint any priest it wishes to the episcopacy for any rite it chooses. Ordinarily though, it appoints a bishop for the rite to which the new bishop has always belonged. Bi-ritual priests are priests who have been given permission to celebrate the liturgy in more than one rite. The priests themselves belong to only one rite.

The dictionary defines bread as "a baked food made of dough or batter, containing flour or meal, milk or water, and often yeast or another leavening agent." In the Eastern Church, leavened bread is used. In the Western Church we use unleavened bread. In both cases, what is used fulfills the definition of bread.

There are differences allowed in the theology found in different rites, provided that they do not contradict what the Church has taught infallibly.

This is no different from allowing differences of thought on theological questions within the Latin rite—as long as they don’t contradict what Rome has mandated. For example, Jesuits tend to disagree with Dominicans on certain issues regarding grace and predestination, but Rome has permitted these differing opinions, so along as neither is opposed to the one true faith.

It is perfectly fine for a Western Catholic to participate in a Catholic Eastern-rite Liturgy, though one must be sure that it is truly Catholic, celebrated in communion with the Holy See.

By the way, "hearing" Mass is not an adequate idiom for our participation in the Eucharistic liturgy. To hear is to be passive, and we are meant to participate actively in the Mass. We are invited to unite ourselves with the Lord in his sacrificial prayer to the Father. When the priest says, "Through him, with him and in him, in the unity of the Holy Spirit, all glory and honor is yours, almighty Father, for ever and ever," the faithful answer, "Amen." That Amen makes Christ’s prayer ours as well.

The Catholic religion is the religion of the Catholic Church—i.e., that group of churches in communion with the pope. If a group isn’t in communion with the pope, it isn’t part of the Catholic Church.

Within the Catholic Church there are a number of individual churches, sometimes called rites. One of these is the Roman rite or Roman church. It includes most of the Catholics in the Western world. A Roman Catholic is a Catholic who is a member of the Roman rite.

There are many Catholics in the East who are not Roman Catholics, such as Maronite Catholics, Ukrainian Catholics, and Chaldean Catholics. These are all in communion with the pope, but they are not members of the Roman rite, so they are not Roman Catholics.

The Roman rite is not stricter than these other rights. They are equal. They all teach the same faith; it is only local customs that are different among them.

In the Eastern rites of the Church it is common for married men to be ordained to the priesthood. Further, in the Latin rite there are a few married men, converted ministers from other faiths, who are ordained to the Catholic priesthood. This, however, is not common. Finally, in neither the Latin rite nor the Eastern rites do priests (or deacons) marry after they have been ordained, except in extraordinary circumstances.

The reasons Latin rite priests can’t marry is both theological and canonical.

Theologically, it may be pointed out that priests serve in the place of Christ and therefore, their ministry specially configures them to Christ. As is clear from Scripture, Christ was not married (except in a mystical sense, to the Church). By remaining celibate and devoting themselves to the service of the Church, priests more closely model, configure themselves to, and consecrate themselves to Christ.

As Christ himself makes clear, none of us will be married in heaven (Mt 22:23–30). By remaining unmarried in this life, priests are more closely configured to the final, eschatological state that will be all of ours.

Paul makes it very clear that remaining single allows one’s attention to be undivided in serving the Lord (1 Cor 7:32–35). He recommends celibacy to all (1 Cor 7:7) but especially to ministers, who as soldiers of Christ he urges to abstain from "civilian affairs" (2 Tm 2:3–4).

Canonically, priests cannot marry for a number of reasons. First, priests who belong to religious orders take vows of celibacy. Second, while diocesan priests do not take vows, they do make a promise of celibacy.

Third, the Church has established impediments that block the validity of marriages attempted by those who have been ordained. Canon 1087 states: "Persons who are in holy orders invalidly attempt marriage."

This impediment remains as long as the priest has not been dispensed from it, even if he were to attempt a civil marriage, even if he left the Church and joined a non-Catholic sect, and even if he apostatized from the Christian faith altogether. He cannot be validly married after ordination unless he receives a dispensation from the Holy See (CIC 1078 §2, 1).

While Jason Evert makes an interesting response to the question regarding the theology behind the Byzantine rite’s prayer for the saints, something much simpler would do the job.

Not only the Roman rite suffers from poor translations—so does the Byzantine, and the case at hand is a prime example. The original Greek for this part of the Divine Liturgy speaks of engaging in the Eucharistic action and prayer " along with Mary, etc." or " in the company of . . . " The Slavonic is a shade off, and since the English text was taken from that, rather than from the original Greek, the English is even more off.

Seen in this light, the theology behind the mention of the saints in Eastern anaphoras is no different from that found in the anaphoras of the West, wherein we find acknowledgement that our offering of the Eucharistic Sacrifice is done while "commemorating" (Roman Canon) or "in union with" (the other Eucharistic Prayers) the Blessed Virgin and all the saints. So, once more, we see the importance of an accurate translation.