Dating Easter

Passover vs Easter Dates

Date of Easter 2011-2015

  • 2011 - Sunday, April 24th
  • 2012 - Sunday, April 8th
  • 2013 - Sunday, March 31st
  • 2014 - Sunday April 20th
  • 2015 - Sunday April 5th
  • 2011 - Sunday, April 24th (same)
  • 2012 - Sunday, April 15th
  • 2013 - Sunday, May 5th
  • 2014 - Sunday, April 20th
  • 2015 - Sunday, April 12th
  • 2011 - April 18-26
  • 2012 - April 6-14
  • 2013 - March 25-April 2
  • 2014 - April 14-22
  • 2015 - April 3-11

The Last Supper, three days before Easter Sunday, is generally assumed to have coincided with the Seder meal at the Jewish festival of Passover (Pesach)*.

Three days before Sunday is Thursday. Why then, don't Christians regularly hold Maundy Thursday commemorations of the Last Supper when Jews celebrate Passover? The two coincide very occasionally.

Maundy (Thursday) comes from mandatum = command. John 13:34:
Mandatum novum do nobis ut diligatis invicem,
I give you a new command -- to love one another

The answer is complicated, rooted in two millennia of history, and based partly on the difficulties of calculating dates according to the Jewish calendar, and partly on the desire to forge a new and separate Christian identity.

According to the Jewish calendar (like the ancient Roman Kalends), the beginning of each month corresponds with the new moon. Two weeks later is the full moon (Roman Ides). Solar and lunar months don't match, and, over time, the religious festivals would fall in the wrong season were it not for the adoption of extra (or intercalary) months.

This is the very problem Julius Caesar faced when he reformed the Roman calendar. The Jewish time-keeping system uses what is known as the Metonic Cycle, which allots 235 lunar cycles/lunations in 19 years. Considering 12 months the norm for each year, this results in an extra month more than once every three years.

Thus, there are 13 months in years 3, 6, 8, 11, 14, 17, and 19 of each Metonic cycle.

The years with extra months can be referred to as leap years. Not all leap (or regular) years are the same. A leap year might have 383, 384, or 385 days while a regular year might have 353, 354, 355 days. Likewise, the number of days in three of the months varies with the year. In his article, Calendars, L.E. Doggett offers more details on the calculations.


Sitting together or assembly.
From the Greek sun=[together] with + hedron=sitting.
It is difficult enough to calculate the proper date for Easter or Maundy Thursday, with so many variables, but the early Christians didn't even have the variables. Instead, they had to rely on the word of the Jewish assembly (Sanhedrin) and its successors (following the destruction of the temple) in Jerusalem, which kept its method of calculating the calendar a secret.

Schism - Splitting of Christianity From Judaism

"At this meeting the question concerning the most holy day of Easter was discussed, and it was resolved by the united judgment of all present, that this feast ought to be kept by all and in every place on one and the same day."
-Eusebius The Life of Constantine III xviii
By the third century, the Christians were no longer a Jewish sect and were calculating the date of Easter without the help of the successors of the the Sanhedrin (the Jewish assembly).


quartus (= fourth) + decimus (= tenth) = 14th
Passover, which fell on the 14th day of the month of Nisan, always fell on a full moon. (Remember that Jewish months like early Roman ones, began at the time of the new moon, so the full moon was two weeks later.) Some Christians, principally those in the East, known as the Quartodecimians, thought Easter, too, should always fall on the 14th day of the lunar month. Others thought Easter should always fall on a Sunday, since that was the original Resurrection Day. This led to conflict: One reason to convene the Nicene Council was to prevent the resulting, threatened schism.

The Council made a kind of compromise decision.

It decreed Easter to be the first Sunday after the Full Moon following the Spring Equinox, March 21, unless that Full Moon fell on a Sunday (in which case Easter would be the following Sunday).

In addition to the perfectly reasonable desire to keep the memorial on the same day of the week as Christ's Resurrection, there were other, ignoble motives for separating the Christian celebration from the Jewish holy day. In his letter to those not at the Nicene Council, the Emperor Constantine spells out some of what we would refer to as anti-semitism:

"Let us then have nothing in common with the detestable Jewish crowd; for we have received from our Saviour a different way."
- Eusebius The Life of Constantine
According to the Jewish calendar, it was possible for a year to have 13 months. Evidently, the Passover month of Nisan was the beginning of the religious year, for Eusebius tells us that the Jews celebrated Passover twice in some years, an indication (to Eusebius) that they didn't know what they were doing:
"They do not possess the truth in this Easter question; for, in their blindness and repugnance to all improvements, they frequently celebrate two passovers in the same year. We could not imitate those who are openly in error."
- Eusebius The Life of Constantine
* Passover occurred on the 14th day of the Hebrew month of Nisan (the first month of the Jewish religious calendar and in the Spring).

Other Reasons for Easter's Date

In "Another View of Easter and Passover," American Sociological Review, Vol. 49, No. 4. (Aug., 1984), John Heeren writes that Jewish leaders supported "the idea that Passover (Nisan 14) should occur after the vernal equinox" and that the Samaritans celebrated Passover after the vernal equinox. The dating of Easter could have been intended to include pagans rather than exclude Jews. it would be fitting for Constantine, as a sun-worshiping pagan, to have selected the vernal equinox, representing the rebirth of the sun, in the same season as the blood-letting pagan Hilaria and Taurobolium festivals.

Further References

  • "Fail-Safe Stellar Dating: Forgotten Phases"
    Harald A. T. Reiche
    Transactions of the American Philological Association (1974-), Vol. 119, (1989), pp. 37-53

Easter Dates Gregorian Calendar

2001-2020 YearWesternOrthodoxPassover
2001 4/154/154/8
2004 4/114/114/6
2007 4/84/84/3
2010 4/44/43/30
2011 4/244/244/19
2014 4/204/204/15
2017 4/164/164/11
Boldface shows years when Western and Orthodox Easters are the same.

The problems of Christian unity and predicting the date of the full moon to determine Easter endured and were even exacerbated by reform based on limited astronomical data.

By the 8th century, there was a chance that, contrary to the ruling of the Nicene Council, Easter might precede or coincide with Passover. Easter had to follow the Vernal Equinox, but the Vernal Equinox no longer fell on March 21.

It was now 3 days earlier. Calculations, at the time, were made using the Julian calendar in which a 3-year cycle of 365 days is followed by a leap year with 366.

It was up to the 16th century Pope Gregory XIII to straighten the Julian calendar and normalize the calculation of Easter in the West. His new cycle was 5,700,000 years long.

But the Orthodox Church resisted the Gregorian calendar and never changed their calculation of Pascha. Instead of Vernal Equinox, they based calculations on March 21, regardless of its relationship to the equinox. The Orthodox Church continued to follow the decree of the Nicene Council using the Julian calendar:

" Easter Day... is the first Sunday after the Full Moon which happens upon or next after the twenty first of March; and if the Full Moon happen upon a Sunday, Easter Sunday is the Sunday after.... The Eastern Church still observes the rule laid down by the Council of Nicea (A.D. 325) and now disregarded by the Western Church, that the Christian Easter shall never precede or coincide with Jewish Passover, but must always follow it. Easter cannot fall earlier than April 5 or later than May 8. The Full Moon used for the purposes of the Easter reckoning is the fourteenth day of a Lunar Moon reckoned according to the ancient Ecclesiastical computation, and not the real Astronomical Full Moon."
* The Service Book of the Holy Orthodox Catholic Apostolic Church.
By 2001 the Western and Eastern Orthodox churches had hoped to reconcile their Easter dates using advances in astronomical information. Using the Gregorian calendar dates, the Orthodox Easter is still no "earlier than April 5 or later than May 8." Although the dates still differ, the 15th of April in 2001 was the correct date according to both calendars, and frequently the dates now correspond.
"According to the proposal [of the World Council of Churches], churches would continue to follow the current formula to calculate the date of Easter, but with the assistance of the most accurate astronomical scientific knowledge available. This would overcome the previous division, under which both traditions insisted upon retaining their old methods for calculating the date, even though they are not always completely faithful to formula laid down by the early church."
- A 1997 move for a common Easter date

Arian Controversy and the Council at Nicea
Early Church
Early Church Trivia
URL =] First Council of Nicea
Dates of Orthodox Easter
[URL =] Dates of Passover

* [URL = <>]