Date of Orthodox Easter

On a different thread in the Eastern Christianity forum, I asked a question trying to figure out how the Orthodox calculate their Easter date; But I didn’t find a succesful answer. :frowning: So, I’m asking the question here in the Apologetics forum…

Catholics celebrate Easter on the first Sunday after the first full moon of Spring…

  • Spring is defined at starting on March 21st
  • Full moon is predicted using a formula, albeit slightly inaccurate
    (The first full moon of Spring is an attempt to correlate Easter with the Jewish Passover, which was when Jesus was crucified.)

Now, why is it that the Orthodox are so different? Sometimes their Easter falls on the same days as ours, othertimes it is 5 weeks later.

I would really appreciate it if someone could provide me with a link, or an explanation, that defines exactly how the Orthodox calculate the Easter date.

Hi Charlie,

The Eastern Church has chosen to celebrate Easter on the Sunday following Jewish Passover. Because the Jews follow a lunar (moon) calendar and we follow a solar (sun) calendar, the two celebrations don’t always coincide.


Do they not also use the Julian Calendar for dates?

My Greek Orthodox friend said that Eastern and Western Easter is the same date every four years.

Yes it’s true that the dates fall on the same date time to time.
However I don’t believe that is it always every 4 years.

For example THIS year (2007) both East and West will celebrate Easter on Apirl 8th.

The next time this will happen will be 2010, 2011, 2014, and 2017 The following link list dates from now (2007) to 2023.

The above link list 6 more years after 2017 and within those 6 years there is no dates that are the same.

The following link list Easter dates from 1990-2050

After 2017 the next time East and West will celebrate Easter the same day is in the year 2025. That is a gap of 8 years.

The reasoning the second link give is lame. I believe there more to it. However it does show the dates.

That is interesting. I still do not understand why nobody was able to explain it well on the Eastern Christianity forum where the OP originally posted the question.:confused:

Hi St Julie,

Some use the Julian and others use the Gregorian calendar throughout the year, but use the Julian calendar to reckon the date of Easter.

My above posts reflects what I have been told by some Greeks. But after reading up on the question I am no longer sure.

There almost was an agreement from all Christians to use the same way of reckoning for Easter, but it was killed by the Russians, who have had a schism on this question.


Disobedience and division does not come from God.

Having a division for a reason such as this is a scandal. It has gone on too long. It is more than time the CC & EO Churches became united once more.

Maybe none of them know? Heck, I did know and understand how we determine Easter even though I was told by the Pastor. There some discrepancies in dates based on what he said so I did some searching and found this:

Who would have thought that the United States Navy would be able to give a concise and exact explanation on how Easter is calculated?

Maybe the Navy understands astronomy so well since the sailors relied on the sun, moon and stars to navigate before modern technology was developed?

ah yes relying on the God’s in the air to guide them…:smiley:

Do you have any idea about the implications of what you are saying?

There are Catholic churches already following the Orthodox dating of Easter! Would you like the rest to follow their example?


Umm, No. No Russian schism about Easter.

Doesn’t NASA employ the Julian Calendar for any astronomical work?

Dating Pascha in the Orthodox Church

Hi Fr Ambrose,

Umm, No. No Russian schism about Easter.

This article talks at length about Old Calendarists and New Calendarists in Russia.


I think you’re thinking of Julian days and Julian dates, which have no direct connection to the Julian calendar.

OK… firstly the poster said there is a schism in the Russian Church about Easter. There isn’t. Apart from the Church of Finland, all the Orthodox Churches have a united date for Easter.

There are NO New Calendarists in Russia itself. Everybody uses the Old Julian Calendar for church life.

But in the UK the Russian Church has given permission for a small number of convert parishes to use the Gregorian Calendar.

Thank you, Fr., for clarifying this.

Oopss… l was supposed to post this into the Apologetics forums, instead I placed it in the Non-Catholic Religions forums… oh well…

Hi Verbum,

I’ve heard something about Orthodox Easter following Jewish Passover; But Jewish Passover is a week long festival. I’m confused as to whether it must follow when Passover is completely finished, or whether is must follow only the first day of Passover.

Hi St Julie,

I think there is more to it than that; I think the Orthodox have different ways of calculating the full moon (because the catholic way is a little inaccurate), and I think Orthodox take into consideration Jewish Passover.

Perhaps the Julian Calendar is used to reckon the vernal equinox (which the Catholics use Mar 21st but Orthodox may use Apr 3rd).

I agree, Eileen; We are standing as a divided witness to Jesus Christ. This is why I’m so interested in understanding the different formulas for calculating Easter date, so that we can be confident in our discussions.

Hi Hesychios,

If I can understand how Orthodox calculate Easter date, and if I agree with their reasoning for doing so, then I guess I would like to see the rest following their example.

But if the Orthodox have an ancient, inaccurate, wrong and, dare I say, stubborn calcuation, well then… no thanks.

Thanks, Fr Ambrose; (Are you really a priest?)

From what I can gather in that link, the differences are as follows…
i) Catholics use Mar 21st as the vernal equinox, whilst Orthodox use Apr 3rd (due to different calendar reckoning)
ii) Catholics use an 84yr cycle in predicting the full moon dates, whilst the Orthodox use a 19yr cycle.

But I think there is more to it; The article doesn’t cover whether or not Jewish Passover is taken into consideration. Also, I understand that in the 1920’s, the Orthodox Church revised the calculation of the Easter date… and I’m not sure if that article has taken that into consideration.

Oh well… I guess I just have to keep looking.

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