How is the Easter date derrived from Jewish passover?

[Dimitris]

Hallo!

We didn't yet celebrate Easter 2009, but I am already thinking of Easter 2010. ;-)

As far as I know, the main reason for the different Easter dates between Eastern and Western Churches is because we, the Orthodox, observe the canons of the first council of Nicaea, which state Pascha has to be the sunday after the Jewish Passover. For example, according to http://en.wikipedia.org/wiki/Passover Passover in 2009 is from April 8 to April 15, therefore we celebrate Easter on the sunday after, which is April 19. But in 2010, Passover is from March 29 to April 5. So Easter should be on April 11. But actually we will celebrate it on April 4.

Does anyone know why? I think, the reason is the "νομικόν φάσκα" (nomikon faska), but I didn't find any information, what "nomikon faska" actually means, how it is calculated and how it is related to Passover. Does anyone have further information?

Kind regards,
Dimitris

[Christopher Dombrowski]

Hallo!

We didn't yet celebrate Easter 2009, but I am already thinking of Easter 2010. ;-)

As far as I know, the main reason for the different Easter dates between Eastern and Western Churches is because we, the Orthodox, observe the canons of the first council of Nicaea, which state Pascha has to be the sunday after the Jewish Passover. For example, according to http://en.wikipedia.org/wiki/Passover Passover in 2009 is from April 8 to April 15, therefore we celebrate Easter on the sunday after, which is April 19. But in 2010, Passover is from March 29 to April 5. So Easter should be on April 11. But actually we will celebrate it on April 4.

Does anyone know why? I think, the reason is the "νομικόν φάσκα" (nomikon faska), but I didn't find any information, what "nomikon faska" actually means, how it is calculated and how it is related to Passover. Does anyone have further information?

Kind regards,
Dimitris

I could have sworn that the Julian Pascha was calculated not in reference to the Jewish Passover.

[Kosta]

At the time of Nicea the jews had discrepancies as to when passover should be celebrated. Some years they celebrated their passover before the vernal equinox, thus the canons state Pascha cannot be celebrated before the vernal equinox with the jews.

Nicea did take the passover into consideration but not the disfunctional way the jews of the diaspora calculated at that time. The council of Nicea decreed that Pascha is to be celebrated on the Sunday AFTER the first full moon which follows the vernal equinox. The jewish passover takes place on the first full moon, so if the full moon falls on a sunday, Pascha is moved to the next Sunday. Thus Pascha never falls on the same date as the start of the jewish passover, but may fall on a sunday before the end of passover

The other factor is that the jewish solar calendar is currently 6 1/2 minutes off per year while the julian calendar is about 11 minutes off. This makes both calendars lose days compared to the gregorian, but the julian at a faster rate than the jewish calendar. It also affects the set date for the vernal equinox between all 3 calendars.

The jewish calendar was standardized in 359 a.d. and has adopted the same 19 year cycle (Known as the metonic cycle) as we do.
Hypothetically if the west, the Orthodox, and the jews all used the same day for setting the vernal equiniox, there would be a few times where the western easter would still fall before the passover, because the papal calculation uses an 84 year cycle. Since the jews use the same 19 year cycle as we do, this discrepancy would be avoided.

With that said, im going to make a kind of unbelieveable claim, pertaining to the original post. I think Pascha falling on April 4 next year may be due to an astronomical error! If the vernal equinox is April 3 (march 21 julian) Pascha would be calculated using the next full moon following April 3. If the full moon were to fall on April 4, which in 2010 is a sunday. Then Pascha would be moved up, and fall on the next sunday. I dont think its the end of the world, the canons emphasizes the forbidding of celebrating Pascha before the equinox (wth the jews) more than anything. It does seem though that the full moon falls on the same day as the vernal equinox next year, which means the powers that be didnt take into account the full moon which falls AFTER the equinox, not on the same day as it. But maybe im all wrong, if so correct me please.

[Olga]

The date of Jewish Passover for 2010 is March 3, from what I've gathered. This is very, very early for Passover (normally it falls in early to mid-April), but it does explain why Orthodox Easter next year will be so early, and coincide with western Easter.

[Kosta]

The date of Jewish Passover for 2010 is March 3, from what I've gathered. This is very, very early for Passover (normally it falls in early to mid-April), but it does explain why Orthodox Easter next year will be so early, and coincide with western Easter.

But if the vernal equinox falls on April 3 (March 21 julian when adding the 13 days that have accrued), i dont see how Pascha 2010 can fall on April 4 without some error. It means Pascha can never fall before April 3 but neither before April 5. From what i've read its the full moon FOLLOWING April 3, not on or before it. Example: vernal equinox falls on April 3 (friday), the first full moon falls on April 4 (saturday), then Pascha would be on April 5.

If the vernal equinox and a full moon coincide on April 3, the paschal calculation disregards it. Making the first full moon fall 28 days later.

Theres something im missing.

[Herman Blaydoe]

There are several artificialities built into the calculations. For example, the calculations assume that the equinox always happens March 21. Sometimes it happens March 20. Perhaps this is one of those cases?

[Fr Raphael Vereshack]

The date of Jewish Passover for 2010 is March 3, from what I've gathered. This is very, very early for Passover (normally it falls in early to mid-April), but it does explain why Orthodox Easter next year will be so early, and coincide with western Easter.

One of our senior priests posted to our lists about this a few months ago.

I'm quite sure the point was that the date of the Jewish Passover that we use for dating Pascha is by this time purely notional.

ie it does not coincide with the actual date of Passover as it is presently computed.

Perhaps if Fr David remembers this post he would recall more details.

In Christ- Fr Raphael

[Dimitris]

So that means, if the wonder of the Holy Light is not working next year it does not necessarily mean the end of world, but maybe simply the Easter date was not calculated correctly.