Recently Pope Francis repeated an idea he has been floating for some time: setting a common date for Easter. Catholics and Eastern Orthodox mark Easter on different dates because the Orthodox use a different calendar (the Julian, which is 13 days out-of-sync from the sun) and formula to fix Easter. What seems to be firing Francis in 2025 is that the date for Easter – April 20 – coincides this year in East and West and that 2025 is the 1,700^th anniversary of the Council of Nicaea which, among other things, fixed how we calculate Easter.

It is claimed that fixing a common Easter would promote Catholic-Orthodox unity, foster ecumenism, and carry out an idea of Vatican II. I think those claims are exaggerated, and I offer three bundles of reasons why:

First, it abandons both Churches’ traditions. The usual “solution” to the divergence of Easter is to peg Easter to some fixed Sunday, the second or third Sundays of April being the leading candidates. That “solution” does not fix the cause of the underlying problem: some Orthodox churches continue to cling to the Julian Calendar for liturgical purposes. The Julian Calendar is out-of-alignment with the sun by almost half a month.

Catholics peg Easter to the Sunday after the first full moon of Spring. The question is when Spring has sprung. If “Spring” is an astronomical event, i.e., the vernal equinox, then no problem. But if “Spring” is a calendrical event based on when it should begin, and your calendar is 13 days misaligned from the sun, you’ll likely come up with a different “first” Sunday of Spring. Some Orthodox also maintain that Easter must follow the celebration of Passover.

By tying Easter to a fixed Sunday, both the Catholic and Orthodox Churches would abandon how they have determined Easter for 1,500+ years in order to produce a deliverable for the professional ecumenists.

Second, it poses theological questions — two in particular. Number one: the common Easter proposal severs the relationship of Easter to Passover, a nexus prominent in all the Gospels (albeit with some disputes as to the connection between the first Holy Thursday/Good Friday and the Passover in the year Jesus was crucified). To attach Easter to the second or third Sundays of April would formally disconnect from Passover when West and East observe Easter (for Catholics, from the paschal moon, which is connected with Passover; for some of the Orthodox, from their insistence that Passover precede Easter). The ecumenical “unity” advanced with the Orthodox would be bought at the cost of interreligious disconnect with our elder Jewish brothers in the faith as well as our own recognized heritage that Passover and Easter are interrelated. Indeed, the whole reason the Council of Nicaea grappled with how to fix Easter was the “Quartodeciman” controversy, the view among some Christians that Easter should coincide with Passover regardless of the day of the week on which Passover fell.

If some Orthodox can forego the connection between Passover and Easter — something other Orthodox to date have declined to do — then it raises question number two: why not just adopt the Gregorian Calendar? All Orthodox majority countries did that for civil purposes at least a century ago. A number of Orthodox churches also have adopted it for liturgical purposes. The biggest holdouts for the Julian Calendar include also the biggest autocephalous Orthodox Church: the Russian.

One must ask: why adhere to a calendar that has been scientifically outdated for centuries, if not out of anti-Catholic animus? Even most Protestant countries finally adopted the Gregorian Calendar by the 18^th century; it took the arrival of the 20^th century for some Orthodox states to get on board.

Behind this is not just anti-Catholic animus (though, to the degree that lingers, one must ask just how much ecumenical unity is going to be achieved beyond a few professional ecumenists’ salons) but a deeper question: the relation of faith and reason. The Church reformed the Julian Calendar with the Gregorian because reason showed the sun in the heavens was not where the wall calendar said it should be. And I would suggest that faith/reason remains an Orthodox challenge.

Without tackling the calendar problem, we might fix a common Easter. But if you don’t reform the calendar, how does each side know when the “second Sunday of April is?” Why might determining that date be a problem? Because if you set a common Easter without having a common calendar, you are not going to have a common Christmas.

Easter is a moveable feast because the Sunday after the first full moon of Spring can occur anywhere between March 22 and April 25. Christmas is fixed: it falls on December 25. But without a common calendar to know when December 25 is, Julian December 25 becomes Gregorian January 7. Is Francis’s theological mountain laboring to produce a Christmas molehill? Will we have a “common Easter” and an “uncommon Christmas?” Won’t that be an “ecumenical scandal,” too?

It seems the problem here is pressure to have something to do for this “providential” (Francis’s word) coincidence of Easter in 2025, the Holy See reverting to “anti-clerical” Francis’s clerical posture of decreeing something, regardless of how it does or does not make sense against a broader set of issues. Where are the “dialogues” within the Catholic Church about this major departure from 15 centuries of practice? Has the Spirit not decided to hold any conversations on the subject? Or is such a momentous change to be grounded in a few words about “launch[ing] bold initiatives for a common date for Easter” buried in paragraph 139 of the last Synod’s final document?

Third, hijacking Vatican II. Justification for this “bold initiative” is often hung on the appendix to the Constitution on the Sacred Liturgy, Sacrosanctum Concilium. The Council Fathers, at the very end of the document, acknowledge “the wishes… [of] many concerning the assignment of the feast of Easter to a fixed Sunday…” It says the Catholic Church “would not object” if “those whom it may concern, especially the brethren who are not in communion with the Apostolic See, give their assent.”

That text was largely considered a dead letter because the Orthodox have no mechanism to establish a pan-Orthodox consensus, neither a binding pan-Orthodox synod nor a focal point of unity like the Bishop of Rome. So, how does Francis intend to establish that “assent”? By declaring it? By signing a decree with the Ecumenical Patriarch of Constantinople? Will the Russian Orthodox Church (ROC) concur? (Not likely.) Can anybody pretend “consensus” exists absent the largest autocephalous Orthodox Church being on board? Without ROC consensus, does the “ecumenical unity” of this proposal not have great potential to create an intra-Orthodox schism with potentially lethal consequences in a place like Ukraine with two competing Orthodox jurisdictions (a Ukrainian autocephalous Church recognized by Constantinople versus a Ukrainian Church subservient to the Patriarch of Moscow)? And are all these problems going to be resolved, after 1,500 years, in the roughly 75 days until Easter?

While Vatican II voiced concern about the “assent” of those “not in communion with the Apostolic See,” how will we establish that “assent” among those in communion with the Holy See? Is that “assent” established because the Pope said so? Does that “assent” not need synodal discussion (did you hear Easter raised in all the “listening sessions” around the world)? How is this to be catechized? By “pay, pray, and obey”?

Finally, it’s arguable that what was thought largely a defunct appendix was put into Vatican II not just out of ecumenical concerns but because, in the 1960s, the idea of calendar reform was also occasionally floated. We see that in the Appendix. It speaks not just of a “common Easter” (a moveable Easter makes much of the rest of the liturgical calendar move, and that’s not fixed if moveability extends over eight rather than 33 days) but also of a “perpetual calendar,” i.e., a calendar in which day (Wednesday) and date (January 4) always remain the same. Again, the Council had “no objection,” subject to the proviso that there are no days that are outside the seven-day week, a far greater temptation today than in 1963. But the faith/reason problem again rears its head: No motu proprio will make 365 divide by seven evenly, which means there will be non-day dates or the 365-day year has to be abandoned so that remainder dates without weekdays can be collected and bundled every couple of years (which defeats the idea of a perpetual calendar). In a secular world, I’d bet opening that can of worms will subvert the Judeo-Christian concept of the seven-day week.

Given all these problems, Francis’s “providential” coincidence seems more a temptation than a blessing, one likely to “make a mess” unnecessarily for and in both East and West.