Reader Question: Is the Date of Easter Related to Passover?

A reader writes:

Eastern Orthodox Easter is NEVER celebrated before Passover. Christ rose from death AFTER Passover. How can we, as modern Christians, celebrate His resurrection before the Passover?

This is a question that I have discussed from a number of different angles over the past two years, yet readers remain confused. The problem is that there is much misinformation and many misconceptions about three things:

1. How the date of Easter is calculated
2. The relationship between the Christian celebration of Easter and the modern Jewish celebration of Passover
3. The reason why Western Christians (Catholic and Protestant) and Eastern Christians (Orthodox) usually (though not always) celebrate Easter on different dates.

So settle in, because it's time to provide the definitive answer to all three questions, and that's going to take a while.

How Is the Date of Easter Calculated?

The reader seems to be assuming that Eastern Orthodox and Western Christians celebrate Easter on different days because the Orthodox take into account the date of the modern Jewish Passover. That's a common misconception--so common, in fact, that Archbishop Peter, the bishop of Diocese of New York and New Jersey of the Orthodox Church in America, wrote an article in 1994 to dispel this myth.

That same year, the Antiochian Orthodox Christian Archdiocese of North America published an article entitled "The Date of Pascha" (the word used by Eastern Christians, both Catholic and Orthodox, for Easter, and a word which will be important to this discussion). That article, too, was an attempt to dispel the widespread yet mistaken belief among Orthodox Christians that the Orthodox calculate the date of Easter in relation to the modern Jewish celebration of Passover.

As more evangelical Protestants and Catholics have developed an interest in Eastern Orthodoxy (especially in the United States) over the past few decades, that misconception has spread beyond the Orthodox. In years such as 2008, when the Western celebration of Easter came before the Jewish celebration of Passover while the Eastern celebration came after, that misconception has caused great confusion--and even anger at those (myself included) who have tried explain why the situation occurred. (See the comments on my March 7, 2008, blog post "Reader Question: Why Does Easter Come Before Passover This Year?" for examples of that confusion and anger.)

Which brings us back to the beginning: How is the date of Easter calculated? Here's where things get very interesting, because, with only very minor differences, both Western and Eastern Christians calculate the date of Easter the same way.

The formula for calculating Easter was set down at the Council of Nicaea in 325--one of the seven ecumenical councils accepted by both Catholics and Orthodox, and the source of the Nicene Creed that we recite every Sunday at Mass. It is a fairly simple formula:

Easter is the first Sunday that follows the paschal full moon, which is the full moon that falls on or after the spring equinox.

For calculation purposes, the full moon is always set at the 14th day of the lunar month (the lunar month begins with the new moon). This is called the ecclesiastical full moon; the astronomical full moon may fall a day or so after or before the ecclesiastical full moon.

The Relationship Between Easter and Passover

Notice what isn't mentioned at all in the formula set down at the Council of Nicaea? That's right: Passover. And with good reason. As the Antiochian Orthodox Christian Archdiocese of North America rightly states in "The Date of Pascha":

Our observance of the Resurrection is related to the "Passover of the Jews" in a historical and theological way, but our calculation does not depend on when the modern-day Jews celebrate.

What does it mean to say that Easter is related to Passover in an "historical and theological way"? In the year of His Death, Christ celebrated the Last Supper on the first day of Passover. His Crucifixion occurred on the second day, at the hour when the lambs were slaughtered in the Temple at Jerusalem. We call the first day "Holy Thursday" and the second day "Good Friday."

Thus, historically, Christ's Death (and therefore His Resurrection) are related in time to the celebration of Passover. So if Christians wanted to celebrate the Death and Resurrection of Christ at the same point in the astronomical cycle as it occurred historically, they now knew how to calculate it. They didn't need to rely on the calculation of Passover (their own calculation or anyone else's); they could--and did--calculate the date of Christ's Death and Resurrection for themselves.

Indeed, around 330, the Council of Antioch clarified the Council of Nicaea's formula for calculating Easter. As Archbishop Peter of the Orthodox Church in America mentions in his article:

These canons condemned those who celebrated Easter "with the Jews." This did not mean, however, that the dissidents were celebrating Easter on the same day as the Jews; rather, that they were celebrating on a date calculated according to the synagogal computations.

But what's the big deal? As long as the Jews calculate the date of Passover properly, why can't we Christians use their calculation to determine the date of Easter?

There are three problems. First, as I've mentioned above, it's unnecessary. Easter can be calculated without any reference to the Jewish calculation of Passover, and the Council of Nicaea decreed that it should be done so. Second, to rely on the calculation of Passover when calculating Easter gives control over a Christian celebration to non-Christians. And third (and related to the second), after the Death and Resurrection of Christ, the continued Jewish celebration of the Passover no longer has any significance for Christians.

This is where the theological point comes in. What does it mean to say that Easter is related to Passover in a theological way? It means that the Passover of the Jews was a "foretaste and promise" of the Passover of Christ. The Passover lamb was a type (a symbol) of Christ. But now that Christ has come and offered Himself as our Passover Lamb, the symbol is no longer needed.

Remember, Pascha, the Eastern word for Easter? It means the Passover lamb. As the Antiochian Orthodox Christian Archdiocese of North America notes in "The Date of Easter," "Christ is our Pascha, our Passover Lamb, sacrificed for us."

In the Latin Rite of the Catholic Church, during the stripping of the altars on Holy Thursday, we sing the "Pange Lingua Gloriosi," a hymn composed by St. Thomas Aquinas. In it, Aquinas, following Saint Paul, explains how the Last Supper becomes the Passover feast for Christians:

On the night of that Last Supper,
seated with His chosen band,
He the Paschal victim eating,
first fulfills the Law's command;
then as Food to His Apostles
gives Himself with His own hand.

Word-made-Flesh, the bread of nature
by His word to Flesh He turns;
wine into His Blood He changes;
what though sense no change discerns?
Only be the heart in earnest,
faith her lesson quickly learns.

The last two stanzas of the "Pange Lingua" are known as the "Tantum Ergo Sacramentum," and the first of the two makes it clear that we Christians believe that there is only one true Passover, that of Christ Himself:

Down in adoration falling,
Lo! the sacred Host we hail;
Lo! o'er ancient forms departing,
newer rites of grace prevail;
faith for all defects supplying,
where the feeble senses fail.

Another common translation renders the third and fourth lines thus:

Let all former rites surrender
to the Lord's New Testament.

What are the former rites here mentioned? The Passover of the Jews, which has found its completion in the true Passover, the Passover of Christ.

In his homily for Easter Sunday 2009, Pope Benedict XVI concisely and beautifully summed up the Christian understanding of the theological relationship between the Passover of the Jews and Easter. Meditating on 1 Corinthians 5:7 ("Christ, our Paschal lamb, has been sacrificed!"), the Holy Father said:

The central symbol of salvation history—the Paschal lamb—is here identified with Jesus, who is called “our Paschal lamb”. The Hebrew Passover, commemorating the liberation from slavery in Egypt, provided for the ritual sacrifice of a lamb every year, one for each family, as prescribed by the Mosaic Law. In his passion and death, Jesus reveals himself as the Lamb of God, “sacrificed” on the Cross, to take away the sins of the world. He was killed at the very hour when it was customary to sacrifice the lambs in the Temple of Jerusalem. The meaning of his sacrifice he himself had anticipated during the Last Supper, substituting himself—under the signs of bread and wine—for the ritual food of the Hebrew Passover meal. Thus we can truly say that Jesus brought to fulfilment the tradition of the ancient Passover, and transformed it into his Passover.

So the Council of Nicaea's prohibition on celebrating Easter "with the Jews" has a deep theological meaning. To calculate the date of Easter with respect to the modern Jewish celebration of Passover would imply that the continued celebration of the Passover of the Jews, which was only ever meant to be a type and symbol of the Passover of Christ, has meaning for us as Christians. It does not. For Christians, the Passover of the Jews has found its completion in the Passover of Christ, and, like "all former rites" it must "surrender to the Lord's New Testament."

It's the same reason why Christians celebrate the Sabbath on Sunday, rather than retaining the Jewish Sabbath (Saturday). The Jewish Sabbath was a type or symbol of the Christian Sabbath--the day that Christ rose from the dead.

The Real Reason for the Difference in the Date of Easter Between East and West

So, if all Christians calculate Easter the same way, and no Christians calculate it with reference to the date of Passover, why do Western Christians and Eastern Christians usually (though not always) celebrate Easter on different dates?

This should be the easiest of the three questions to answer, but it is often the hardest for people to understand. In fact, it's largely because people don't understand what I'm about to explain that they look around for other explanations for the difference in dates, and come erroneously to believe that it must have something to do with the date of Passover.

While there are minor differences between East and West in how the date of the paschal full moon is calculated that do affect the calculation of the date of Easter, the primary reason why we celebrate Easter on different dates is because the Orthodox continue to calculate the date of Easter according to the older, astronomically inaccurate Julian calendar, while Western Christians calculate it according to the much more astronomically accurate Gregorian calendar (the calendar we all use in daily life).

Here's how the Antiochian Orthodox Christian Archdiocese of North America explains it in "The Date of Easter":

Unfortunately, we have been using the 19-year cycle in calculating the date of the Resurrection ever since the fourth century without actually checking to see what the sun and moon are doing. In fact, besides the imprecision of the 19-year cycle, the Julian calendar itself is off by one day in every 133 years. In 1582, therefore, under Pope Gregory of Rome, the Julian Calendar was revised to minimize this error. His "Gregorian" calendar is now the standard civil calendar throughout the world, and this is the reason why those who follow the Julian Calendar are thirteen days behind. Thus the first day of spring, a key element in calculating the date of Pascha, falls on April 3 instead of March 21.

We can see this same effect of the use of the Julian calendar in the celebration of Christmas. All Christians, East and West, agree that the Feast of the Nativity is December 25. Yet some Orthodox celebrate the Feast of the Nativity on January 7. That doesn't mean that there is dispute between Christians (or even just among Orthodox) about the date of Christmas: Rather, December 25 on the Julian calendar currently corresponds to January 7 on the Gregorian one, and some Orthodox continue to use the Julian calendar to mark the date of Christmas.

But wait--if there's currently a 13-day difference between the two calendars, shouldn't that mean that our celebrations of Easter should always be 13 days apart? No. Remember the formula for calculating Easter:

Easter is the first Sunday that follows the paschal full moon, which is the full moon that falls on or after the spring equinox.

We've got several variables in there, including the most important one: Easter must always be on a Sunday. Combine all of those variables, and the Orthodox calculation of Easter can vary by as much as a month from the Western calculation.

Doubt No Longer, But Believe

I know that this is a lot of information, and I know that some Christians (especially Orthodox and evangelical Protestants, but even some Catholics) will continue to be skeptical of statements I have made above. But there's no reason to be: You can verify this yourself by reading both Orthodox sources and secular sources, in addition to what I have written.

You can find a good selection of such materials below.

If you have a question that you would like to have featured in our "Reader Questions" series, send me an e-mail at catholicism.guide@about.com. Be sure to put "QUESTION" in the subject line, and please note whether you'd like me to address it privately or on the Catholicism blog.

Catholic Resources Concerning the Date of Easter:

• How Is the Date of Easter Calculated?
• Why Did Easter Come Before Passover in 2008?

Orthodox and Protestant Resources Concerning the Date of Easter:

• "The Date of Pascha," by Archbishop Peter of the Diocese of New York and New Jersey of the Orthodox Church in America
• "The Date of Pascha," by the Antiochian Orthodox Christian Archdiocese of North America
• "Easter Day - how is it worked out?" by the Rev. Bosco Peters

Secular Resources Concerning the Date of Easter:

• "Dating Easter: Passover vs Easter Dates," by N.S. Gill, About.com Guide to Ancient History
• "Dates of Easter, Rosh Hashanah, and Passover," by William H. Jefferys, Harlan J. Smith Centennial Professor of Astronomy (Emeritus) at the University of Texas at Austin
• "Computus," on Wikipedia

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