Questions about the Paschalion

[Megaloskhemos]

Just a curiosity of mine.


So, as I understand it, the Paschalion gives us the date of Easter by calculating the the date of the "Paschal Full Moon" which doesn't actually necessarily coincide with any instance of an astronomically observed full moon at any place on the planet (Or does it? The difference has something to do with the fact that the calendar is inconsistent with astronomy in some way, right?), and placing Easter on the Sunday after that Paschal Full Moon. The way we get the date of the Paschal Full Moon is based on some traditional tables which are on a metonic (~19 year) cycle.

Is this correct? If so, where do the tables of dates for the Paschal Full Moon come from? Whose initial observation are we working from? Does it go back to some ancient Greek astronomer, or is there a theological reason for the pattern?

 

[gzt]

Part of the problem is that the date of the vernal equinox used in the calculation is wrong. Both East and West have lunar calendars which are out of sync with reality. They used the same one until the Gregorian reforms, now the West uses a different one. But they're only off by like two days at most, IIRC (well, the Eastern one might be off by more). So the big difference is that, while they both want the first ecclesiastical full moon on or after March 21st, their definitions of March 21st are different.

 

[Megaloskhemos]

Part of the problem is that the date of the vernal equinox used in the calculation is wrong. Both East and West have lunar calendars which are out of sync with reality. They used the same one until the Gregorian reforms, now the West uses a different one. But they're only off by like two days at most, IIRC (well, the Eastern one might be off by more). So the big difference is that, while they both want the first ecclesiastical full moon on or after March 21st, their definitions of March 21st are different.

Yes, certainly. My question is more concerning the reason for the choice of maintaining the old Roman date of Julian March 21st for the equinox and why we use the equinox in conjunction with the old reckoning of the metonic cycle in the first place. Why is it important to maintain the calculated date which seems inconsistent with the astronomical observations? Is it that we're trying to coincide with the Jewish month of Nisan?

If we keep the Julian March 21st for some important purpose, why use a theoretical full moon as opposed to an actual observed one from a set location?

Why not just use the actual vernal equinox from a particular place on Earth (Jerusalem for instance), then use the next actual astronomically observed full moon from the same place?

 

[buzuxi02]

2010 was the start of a new Paschal Cycle known as the Great Indiction. Basically you multiply the 19 year metonic lunar cycle with the 28 year solar cycle which gives you 532 years. Thus the tables are 532 year cycles and after that they reset to the beginning. Since the julian calendar drifts about 11 minutes every year this equals about 4 days every 532 years.

So in 2010 the vernal Equinox fell on April 2, the full moon on April 3 and Pascha Sunday fell on April 4. 532 years later in the year 2542 the equinox will fall on April 6, the full moon on April 7 and Pascha on April 8.

532 years after that in the year 3074, the equinox will fall on April 10, the full moon on April 11 and Pascha Sunday will be on April 12. In the year 3606 the equinox will fall on April 14, the paschal full moon on April 15 and Pascha Sunday will fall on April 16. I think you get the idea.

The reason you keep a fixed date for the equinox is because it keeps the fixed feasts in proper time proportions with the moveable feasts, since no solar calendar is 100% accurate. This is the problem with the revised julian calendar where fixed feasts have to become moveable feasts in some years (feast of st George) and the 40 days of Pascha sometimes coincides with the Apostles fast. Only by using the same calendar and a fixed date for the equinox can a liturgical calendar maintain its rythmn.

 

[Megaloskhemos]

2010 was the start of a new Paschal Cycle known as the Great Indiction. Basically you multiply the 19 year metonic lunar cycle with the 28 year solar cycle which gives you 532 years. Thus the tables are 532 year cycles and after that they reset to the beginning. Since the julian calendar drifts about 11 minutes every year this equals about 4 days every 532 years.

So in 2010 the vernal Equinox fell on April 2, the full moon on April 3 and Pascha Sunday fell on April 4. 532 years later in the year 2542 the equinox will fall on April 6, the full moon on April 7 and Pascha on April 8.

532 years after that in the year 3074, the equinox will fall on April 10, the full moon on April 11 and Pascha Sunday will be on April 12. In the year 3606 the equinox will fall on April 14, the paschal full moon on April 15 and Pascha Sunday will fall on April 16. I think you get the idea.

Ah, ok. That makes a great deal of sense then, given that the calendar drifts that much. Thank you. However, that leads me to my next question:

The reason you keep a fixed date for the equinox is because it keeps the fixed feasts in proper time proportions with the moveable feasts, since no solar calendar is 100% accurate. This is the problem with the revised julian calendar where fixed feasts have to become moveable feasts in some years (feast of st George) and the 40 days of Pascha sometimes coincides with the Apostles fast. Only by using the same calendar and a fixed date for the equinox can a liturgical calendar maintain its rythmn.

But, doesn't that problem with the Revised Julian calendar only exist because those on the New Calendar still use the old Julian dates for the Paschalion? (I didn't think too far ahead in asking my questions-- this is inevitably a Old/New Calendar issue isn't it?) I guess I'll cautiously ask the question: why is the Paschalion locked to the Julian dates?

 

[gzt]

Short answer: yes, which is why the Gregorian calendar revised both at once. Why are we locked to the Julian dates: there are a lot of reasons, but the biggest is just that we haven't unlocked from them yet.

 

[buzuxi02]

The council of Nicea handed the 'definition' on how to calculate Pascha based on March 21 Julian using the metonic cycle. If actual observation of the Equinox was used, then in the 12th century the empire would have calculated Pascha on the basis that the Equinox fell on March 15th! Likewise today those on the old calendar would see the Equinox on March 8. The Great Fast would eventually sart before Theophania. There was never a time or even intension in the early church to ever use actual observations of the seasons and moons.

The Gregorian Paschalion has been condemned by numerous pan-Orthodox synods. It too has its problems, the equinox sometimes falls on the 20th sometimes the 21st(In some years this will make Easter fall before the 14th moon, etc)

 

[Megaloskhemos]

Short answer: yes, which is why the Gregorian calendar revised both at once. Why are we locked to the Julian dates: there are a lot of reasons, but the biggest is just that we haven't unlocked from them yet.

The council of Nicea handed the 'definition' on how to calculate Pascha based on March 21 Julian using the metonic cycle. If actual observation of the Equinox was used, then in the 12th century the empire would have calculated Pascha on the basis that the Equinox fell on March 15th! Likewise today those on the old calendar would see the Equinox on March 8. The Great Fast would eventually start before Theophania. There was never a time or even intention in the early church to ever use actual observations of the seasons and moons.

The Gregorian Paschalion has been condemned by numerous pan-Orthodox synods. It too has its problems, the equinox sometimes falls on the 20th sometimes the 21st(In some years this will make Easter fall before the 14th moon, etc)

Ah ok, thank you both. I was wondering if there was some theological reason or something else along those lines. Interesting stuff.

Thanks again.

 

[Mockingbird0]

The council of Nicea handed the 'definition' on how to calculate Pascha based on March 21 Julian using the metonic cycle.

No, it didn't. The Council held that all Christians should use the same method, and that it should be independent of the Jewish calendar. The mathematical details were left to be worked out in practice. The most the Council can be said to have done is to have incorporated the Alexandrine computus "by reference" in its decision.

There was never a time or even intension in the early church to ever use actual observations of the seasons and moons.

Yes there was. Peter, bishop of Alexandria, in explaining why his city abandoned the old custom of consulting Jews for the dates of their week of Unleavened Bread and setting Easter to the Sunday of that week, stated

On the fourteenth day of [the month], being accurately observed after the equinox, the ancients celebrated the Passover, according to the divine command. Whereas the men of the present day now celebrate it before the equinox, and that altogether through negligence and error.--Chronicon Paschale

If accuracy were of no importance, why does he complain that the Jewish calendar is not accurate? If the seasons were not a problem, celebrating before the equinox would not have mattered.

Dionysius Exiguus, in his explanation of the Alexandrian computus, insisted that the age of the moon by his tables was more accurate than what was found in the competing tables. He was not in fact correct. The competing tables, though though they sometimes differed from his, were just as accurate. But if accuracy had been of no importance, Dionysius wouldn't have made this boast in the first place.

The Gregorian Paschalion has been condemned by numerous pan-Orthodox synods. It too has its problems, the equinox sometimes falls on the 20th sometimes the 21st(In some years this will make Easter fall before the 14th moon, etc)

This statement makes no sense. The discrepancy between the astronomical and ecclesiastical equinoxes has no effect on the age of the moon.

 

[Mockingbird0]

So, as I understand it, the Paschalion gives us the date of Easter by calculating the the date of the "Paschal Full Moon" which doesn't actually necessarily coincide with any instance of an astronomically observed full moon at any place on the planet (Or does it? The difference has something to do with the fact that the calendar is inconsistent with astronomy in some way, right?), and placing Easter on the Sunday after that Paschal Full Moon. The way we get the date of the Paschal Full Moon is based on some traditional tables which are on a metonic (~19 year) cycle.

Right. The Julian calendar consists of a solar side and a lunar side. The lunar side (the computus or paschalion) was developed over a course of time beginning in the 3rd century. It was adjusted over the course of the next 200 years or so, reaching its final form before 525, when it was described in Latin by Dionysius Exiguus. (The Armenian church never accepted one of the later adjustments, so Armenian Easter is occasionally different from Greek Easter). The Julian lunar tables were accurate to within a day or so at the time they were developed, and have since drifted away from the astronomical facts, so that now, as Roger Bacon put it, "any rustic can see the error in the sky."

Where do the tables of dates for the Paschal Full Moon come from? Whose initial observation are we working from

The first draft of the 19-year Metonic computus is attributed to Anatolius of Alexandria (mid-3rd century). As noted above, Anatolius's cycle was modified over the course of the following centuries, finally stabilizing into the Julian computus that was used by most Christians up until the Gregorian reform.

 

[buzuxi02]

No, it didn't. The Council held that all Christians should use the same method, and that it should be independent of the Jewish calendar. The mathematical details were left to be worked out in practice. The most the Council can be said to have done is to have incorporated the Alexandrine computus "by reference" in its decision.
Yes there was. Peter, bishop of Alexandria, in explaining why his city abandoned the old custom of consulting Jews for the dates of their week of Unleavened Bread and setting Easter to the Sunday of that week, stated If accuracy were of no importance, why does he complain that the Jewish calendar is not accurate? If the seasons were not a problem, celebrating before the equinox would not have mattered.

I'm not sure what your trying to say here. I think we pretty much agree if your saying that Nicea adopted the Alexandrian formula, and that set the Equinox at a fixed date of March 21 using the 19 year lunar cycle. That Pascha is celebrated on the first Sunday after the full moon which falls on or after the vernal equinox, not before it and that actual observations were never used.

Dionysius Exiguus, in his explanation of the Alexandrian computus, insisted that the age of the moon by his tables was more accurate than what was found in the competing tables. He was not in fact correct. The competing tables, though though they sometimes differed from his, were just as accurate. But if accuracy had been of no importance, Dionysius wouldn't have made this boast in the first place.

Regardless, they used tables and not the real observable equinox or moon. For instance (putting aside the few days variation) if the actual observation of the equinox was used, then March 21st would have been accurate till about 355 a.d. After that the equinox would have occured on March 20th on the Julian. Sometime after 490 a.d. it would have been observed on March 19. The historical tables developed in 525 a.d. still used the equinox of March 21 as observed on the julian calendar from the (approx) years 220 to 355, hence the observable Equinox during Nicea.

This statement makes no sense. The discrepancy between the astronomical and ecclesiastical equinoxes has no effect on the age of the moon

.
My correction, in my above post the ecclesiastical fullmoon and the fixed equinox fell on saturdays hence in 2010 April 3rd was the equinox and full moon and Pascha fell the next day on the 4th, and so on.

 

[gzt]

One of the reasons for using tables rather than observations is that you can predict it in advance. The equinox and the full moon are not "days", they're astronomical events. Astronomical events that don't occur on a space of time, but, in fact, a moment. A moment that cannot be predicted to better than within a few minutes, actually. If you base it on actual observations, one of these days the interval is going to straddle midnight and you won't know until it happens what day is, in fact, the equinox. This was one of the big problems with the French revolutionary's reformed calendar, actually. They based the beginning of their year on the equinox and in one of the first years of the calendar the interval straddled midnight. That is bad!

 

[Mockingbird0]

I'm not sure what your trying to say here. I think we pretty much agree if your saying that Nicea adopted the Alexandrian formula, and that set the Equinox at a fixed date of March 21 using the 19 year lunar cycle. That Pascha is celebrated on the first Sunday after the full moon which falls on or after the vernal equinox, not before it and that actual observations were never used.

Earlier you wrote:

There was never a time or even intension in the early church to ever use actual observations of the seasons and moons.

I misunderstood you to mean that it did not matter to them how well, or how badly, their tables approximated the astronomical facts. I see now that you meant only that they used tables to approximate the facts, on which, as you note, we agree.

My correction, in my above post the ecclesiastical fullmoon and the fixed equinox fell on saturdays hence in 2010 April 3rd was the equinox and full moon and Pascha fell the next day on the 4th, and so on.

I understood your post above to mean

The [astronomical] equinox sometimes falls on the 20th sometimes the 21st (In some years this [difference between the astronomical and ecclesiastical equinox] will make [Gregorian] Easter fall before the 14th moon.

I hold the following: The difference between the astronomical and Gregorian ecclesiastical equinoxes can occasionally put Gregorian Easter in a different lunation from astronomical Easter (usually the next lunation after), but it won't by itself cause the Gregorian ecclesiastical full moon to fall before the astronomical full moon.

 

[Mockingbird0]

Both East and West have lunar calendars which are out of sync with reality. They used the same one until the Gregorian reforms, now the West uses a different one. But they're only off by like two days at most, IIRC (well, the Eastern one might be off by more).

Here are the Gregorian calendar dates of the Gregorian and Julian ecclesiastical full moons for 2012:

• 
  Astronomical full moon (start of day at Midnight UT)/Gregorian EFM/Julian EFM
• Jan 9 / Jan 8 / Jan 12
• Feb 7 / Feb 7 / Feb 11
• Mar 8 / Mar 8 / Mar 12
• Apr 6 / Apr 7 / Apr 11
• May 6 / May 6 / May 10
• Jun 4 / Jun 5 / Jun 9
• Jul 3 / Jul 4 / Jul 8
• Aug 2 / Aug 3 / Aug 7
• Aug 31 / Sep 1 / Sep 5
• Sep 30 / Oct 1 / Oct 5
• Oct 29 / Oct 30 / Nov 3
• Nov 28 / Nov 29 / Dec 3
• Dec 28 / Dec 28 / Jan 1 2013

As you suspect, the Julian moon is "off by more". Julian Easter is a week after Gregorian Easter this year because the Gregorian moon is full on Saturday, April 7th, while the Julian moon is not full until the following Wednesday, April 11th.

Why not just use the actual vernal equinox from a particular place on Earth (Jerusalem for instance), then use the next actual astronomically observed full moon from the same place?

An advantage of using tables based on averages, rather than more precise computations, is that they can be constructed even under adverse conditions using simple integer arithmetic.

 

[Mockingbird0]

Posted by buzuxi02 on 4/12/2007 in an older thread (t5148134-2), now closed:

Pascha falls on the first sunday after the first full moon of the vernal equinox. Using the metonic/callipic cycle (19 years or 235 lunar months).

Western Easter does not observe the underlined aspect and uses a different cycle and calendar

I don't know if buzuxi02 still holds to this or not. In any case, it is not true. Gregorian paschalion is a form of the the Metonic cycle.

Easter is always the Sunday after the full moon that falls on or after the vernal equinox on March 21. This full moon may happen on any date between March 21 and April 18 inclusive. If the full moon falls on a Sunday, Easter is the Sunday following....The Golden number indicates the date of the full moon on or after the spring equinox of March 21, according to a nineteen-year cycle."
--Book of Common Prayer, (1979), p. 880. Emphasis added.

Posted by buzuxi02 on 4/12/2007 in the same older thread:

The west uses an 80-something year cycle.

Again, buzuxi02 might no longer hold to this, but since the statement is still in the archive it might as well be addressed. The Roman church used an 84-year cycle at the time of the Nicene Council, and hence this old 84-year cycle was implicitly approved by the Council. However, the Western churches all eventually adopted the 19-year cycle. An 84-year cycle hasn't been used in Western Christianity for over a thousand years.

 

[buzuxi02]

The Roman church used an 84-year cycle at the time of the Nicene Council, and hence this old 84-year cycle was implicitly approved by the Council. However, the Western churches all eventually adopted the 19-year cycle. An 84-year cycle hasn't been used in Western Christianity for over a thousand years.

When did the roman church abandon the 84 year cycle? At the time of Nicea onwards the Roman church used the 19 year cycle. Sometime after the council of Chalcedon when Alexandria was weakened and Rome began being more assertive they tinkered with the paschalion. Of course my primary emphasis on speaking about the 19 year cycle is because no one wants to bring this up in this day and age of ecumenism. Many believe that Nicea only decreed that all should celebrate the great feast on the same Sunday after the vernal Equinox. This false assumption can be seen in a lengthy discussion on the OC.Net message board where those ingenius posters have yet to quote the Fathers and the councils on the topic of the paschalion. There long running thread is full of disinformation.

The earliest reference to the Nicean decree on Pascha is Canon 1 of Antioch held in 341 a.d. It makes no mention of the vernal equinox (i point this out since many think this was the only substantive thing Nicea declared):

Whosoever shall presume to set aside the decree(oros) of the holy and great Synod which was assembled at Nice in the presence of the pious Emperor Constantine, beloved of God, concerning the holy and salutary feast of Easter; if they shall obstinately persist in opposing what was [then] rightly ordained, let them be excommunicated and cast out of the Church; this is said concerning the laity. But if any one of those who preside in the Church, whether he be bishop, presbyter, or deacon, shall presume, after this decree(oros), to exercise his own private judgment to the subversion of the people and to the disturbance of the churches, by observing Easter [at the same time] with the Jews, the holy Synod decrees that he shall thenceforth be an alien from the Church, as one who not only heaps sins upon himself, but who is also the cause of destruction and subversion to many; and it deposes not only such persons themselves from their ministry, but those also who after their deposition shall presume to communicate with them. And the deposed shall be deprived even of that external honour, of which the holy Canon and God’s priesthood partake.

In my previous post I said that Nicea delivered a 'definition' on Pascha and that is what the word 'oros' means. So it was more substantive than a vague canon with a few suggestions. In the above canon the rule that Pascha must fall on the sunday AFTER the full moon but not on the full moon is verified. That is we cannot celebrate Pascha at the same time as the jews, which is precisely what would happen if Pascha was not moved to the following Sunday if the full moon fell on a sunday.

We also have the testimony of the early Fathers who add further details on what Nicea decreed. That is the 19 year cycle. One of the most powerful epistles in what Nicea decreed comes from St Ambrose of Milan to the bishops of Emilia written in 386 a.d:

1. THAT to settle the day of the celebration of the Passover requires more than ordinary wisdom, we are taught both by the Holy Scripture and by the tradition of the Fathers, who, when assembled at the Nicene Synod, in addition to their true and admirable decrees concerning the Faith, formed also for the above-mentioned celebration a plan for nineteen years with the aid of the most skilful calculators, and constituted a sort of cycle to serve as a pattern for subsequent years. This cycle they called the nineteen years' cycle83, their aim being that we should not waver in uncertain and ungrounded opinions on such a |167 celebration, but ascertain the true method and so ensure such concurrence of the affections of all, that the sacrifice for the Lord's Resurrection should be offered every where on the same night.....

Accordingly, since, even after the calculations of the Egyptians, and the definitions of the church of Alexandria, and also of the Bishop of the church of Rome, several persons are still waiting my judgement by letter, it is needful that I should write what my opinion is about the day of the Passover. For though the question which has arisen is about the approaching Paschal day, yet we state what we think should be maintained for all subsequent time, in case any question of the kind should come up.
9. But there are two things to be observed in the solemnity of the passover, the fourteenth moon, and the first month, which is called the month of the new fruits.... We must then keep this law of Easter, not to keep the fourteenth day as the day of the Resurrection, hut rather as the day of the Passion, or at least one of the next preceding days, because the feast of the Resurrection is kept on the Lord's day; and on the Lord's day we cannot fast; for we rightly condemn the Manichaeans for their fast upon this day. For it is unbelief in Christ's Resurrection, to appoint a rule of fasting for the day of the Resurrection, since the Law says that the Passion is to he eaten with bitterness....

14. In times lately past, when the fourteenth moon of the first month fell on the Lord's day, the solemnity was celebrated on the Lord's day next ensuing. But in the eighty-ninth year of the Era of Diocletian,when the fourteenth moon was on the 21th of March, Easter was kept by us on the last day of March. The Alexandrians and Egyptians also, as they wrote themselves, when the fourteenth day of the moon fell on the 28th day of the month Phamenoth, kept Easter on the fifth day of the month Pharmuthi, which is the last day of March, and so agreed with us. Again in the ninety-third year of the Era of Diocletian, when the fourteenth moon fell on the fourteenth day of the month Pharmuthi, which is the 9th of April, and was the Lord's day, Easter was kept on the Lord's day, the 21st day of Pharmuthi, or according to us on the 16th of April. Wherefore since we have both reason and precedent, nothing should disturb us upon this head....
16. Nor do I consider it unreasonable to borrow a precedent for observing the month from the country in which the first Passover was celebrated. For which reason also our predecessors in the ordinance of the Nicene Council thought fit to decide that their cycle of nineteen years should belong to the same month, if one observes it diligently; and they rightly kept the very month of the new fruits, for in Egypt it is in this the first month that the new corn is cut: and this month is the first in respect of the crops of the Egyptians and first according to the Law, but the eighth according to our custom, for the in-diction begins in the month of September. The first of April therefore is in the eighth month. But the month begins not according to vulgar usage, but according to the custom of learned men, from the day of the equinox, which is the 21st of March, and ends on the 21st of April. Therefore the days of Easter have been generally kept as much as possible within these thirty-one days.(Epistle xxiii)

Finally there is St Cyril of Alexandria addressing Pope Leo (Migne Patrologia Latin vol xliv)

Let us carefully examine what the Synod in Nicea decreed with regard to the the calculation of the 14 moons of each month of the 19 year cycle, for at every synod, it has been decreed that no church may do anything at odds with the resolution agreed upon at the Synod of Nicea about Pascha.

 

[Mockingbird0]

When did the roman church abandon the 84 year cycle? At the time of Nicea onwards the Roman church used the 19 year cycle. Sometime after the council of Chalcedon when Alexandria was weakened and Rome began being more assertive they tinkered with the paschalion. Of course my primary emphasis on speaking about the 19 year cycle is because no one wants to bring this up in this day and age of ecumenism. Many believe that Nicea only decreed that all should celebrate the great feast on the same Sunday after the vernal Equinox.

I read the history differently from you. The original practice was to have Easter on the Sunday of Unleavened Bread. When the week of Unleavened Bread would fall in any given year was determined by consulting Jewish neighbors. Beginning in the 3rd century, some Christians began experimenting with independent computations in order to ensure that the festival would fall after the equinox. Rome and Alexandria first tried 8-year cycles. Then Alexandria switched to a 19-year cycle in the mid-3rd century, and Rome to an 84-year cycle sometime before A.D. 300.

The Nicene council's decision was that (1) All the churches should have Easter on the same day, (2) Easter should fall after the equinox and (3) the week whose Sunday was Easter would be computed independently of the Jewish calendar. And that is all. Both the Alexandrian-19 and the Roman-84 met these requirements, so both were implicitly accepted by the Council, as Constantine's letter shows:

I myself have undertaken that this decision should meet with the approval of your Sagacities, in the hope that your Wisdoms will gladly admit that practice which is observed at once in the city or Rome, and in Africa, throughout Italy, and in Egypt...

The earliest reference to the Nicean decree on Pascha is Canon 1 of Antioch held in 341 a.d. It makes no mention of the vernal equinox (i point this out since many think this was the only substantive thing Nicea declared):


"But if any one of those who preside in the Church, whether he be bishop, presbyter, or deacon, shall presume, after this decree(oros), to exercise his own private judgment to the subversion of the people and to the disturbance of the churches, by observing Easter [at the same time] with the Jews, the holy Synod decrees that he shall thenceforth be an alien from the Church"

In my previous post I said that Nicea delivered a 'definition' on Pascha and that is what the word 'oros' means.

"Oros" in the canon refers to the Antiochene canon, not to anything from Nicea.

So it was more substantive than a vague canon with a few suggestions. In the above canon the rule that Pascha must fall on the sunday AFTER the full moon but not on the full moon is verified.

No, it isn't. The canon only refers to (a) unanimity and (b)independence from the Jewish calendar. Mathematical details are not mentioned.

That is we cannot celebrate Pascha at the same time as the jews, which is precisely what would happen if Pascha was not moved to the following Sunday if the full moon fell on a sunday.

Not, it isn't. Because we set our festival independently, our computi define a Christian Nisan and set Easter to the 3rd Sunday of that month: the Sunday of Unleavened Bread by a Christian computation. They make no external reference to any other system, so an accidental coincidence is not prevented from our side. That is what "independent" means. As it happens, according to the rules of the modern Rabbinic calendar, Nisan 14 can never fall on Sunday, Tuesday, or Thursday anyhow, so Easter never coincides with Rabbinic Nisan 14. But this is a rule of the Rabbinic calendar, not of ours.

We also have the testimony of the early Fathers who add further details on what Nicea decreed. That is the 19 year cycle.

Not, it wasn't. The only things Nicea decided were (1) unanimity (2) independence, and (3) the equinox.

One of the most powerful epistles in what Nicea decreed comes from St Ambrose of Milan to the bishops of Emilia written in 386 a.d:

This shows that the error of attributing the 19-year cycle (in its final, post-Nicene form) to Nicea entered Christian discourse early. But it is still an error. Epiphanius, in his description of the Council's decision, (Against the Audians) mentions only the three things enumerated above. He illustrates the concept of independence using the 8-year cycle, not a 19-year cycle.

Rome switched to a 19-year cycle in the 5th century (the Victorian computus), and to the Byzantine computus in the 6th. Older tables continued in use elsewhere for a while, but the Byzantine computus eventually prevailed over all its rivals. The Gregorian computus is merely a reform of the Julian. At the present day, its solar tables are 13 days ahead of the Julian calendar's and its lunar tables are 4 days (sometimes 5) ahead of the Julian calendar's. But otherwise it works in the same way, spanning 19 solar years with 235 lunar months.

 

[buzuxi02]

Sorry but this false, The Fathers attribute these rules to Nicea. The term oros in the antiochan canon is speaking of the 'decree' of Nicea. The reason a misunderstanding is taking place is because the ecumenists are so hard attempting to tell us that St Ambrose and St Cyril simply made it up! The epistle of St Ambrose is available online on tertullian.org. I have never seen any evidence that Rome differed from Alexandria from the time of Nicea. This is only 'assumed' because of some tables devised by Hippolytus, Ambrose is unaware of this even claiming men who know computations were present at Nicea.

We are calculating Pascha independantly of what the jews were doing, whenever the full moon occurs using our caculations, its always the sunday after that not on or before it. On a side note the jews devised their formula in 369 a.d. making their observance more uniform adopting the metonic cycle as well.

The Fathers and the canons speak for themselves.

 

[Mockingbird0]

The term oros in the antiochan canon is speaking of the 'decree' of Nicea.

It is true that the first time the word "decree" occurs in the translation above, it refers to Nicea. The 2nd time, it does not.

The Fathers attribute these rules to Nicea.

Eusebius and Epiphanius do not attribute any specific lunar limits or any particular number of years in a lunar cycle to the council. St. Athanasius made a number of post-Nicene adjustments to the Alexandrian computus in order to achieve more frequent agreement with Rome (see below where I give the examples of the years 333, 343, and 346).

The reason a misunderstanding is taking place is because the ecumenists are so hard attempting to tell us that St Ambrose and St Cyril simply made it up!

Neither Ambrose nor Cyril or Alexandria was alive in 325. We may rationally doubt these later writers if the earlier writers do not support them.

I have never seen any evidence that Rome differed from Alexandria from the time of Nicea.

The evidence for the early form of the supputatio Romana can be pieced together from a number of sources, including the Festal Letters of Athanasius and the Aramaic index to them, the correspondence between bishops of Rome and Alexandria, paschal and consular lists such as the Chronograph of 354, and from compututistical writers of the 4th-6th centuries.

Ambrose is unaware of this even claiming men who know computations were present at Nicea.

Epiphanius "knew computations" somewhat and may have had access to some who attended the council. He nowhere explicitly mentions a 19-year cycle. This is an argument from silence, true, but here the silence speaks loudly. In the case of Ambrose, the reason he needed to write to Aemilia at all was probably because of the disagreement between Alexandria and Rome. The Roman church claimed to have a tradition from St. Peter that Easter should never come after April 21st. Ambrose seems to refer to this when he states that Easter is kept "as much as possible" on or before April 21st. Easter always on or before April 21 is mathematically impossible under Alexandrian rules, but the Roman-84, as scholars have reconstructed it, managed to pull it off most years. In the year 360, one of the years mentioned by Ambrose, Rome according to a consular list appended to the Chronograph of 354 observed April 16th while Milan (according to Ambrose) and Alexandria (according to the Aramaic index to Athanasius's Festal Letters) observed April 23rd.

We are calculating Pascha independantly of what the Jews were doing, whenever the full moon occurs using our caculations, its always the sunday after that not on or before it.

The same is true of the Gregorian calendar. Last year, 2011, for example, the Gregorian and Julian calendars gave the same date because no Sunday intervened between the Gregorian full moon on April 17th and the Julian full moon 5 days later on April 22nd. This year, 2012, the Paschal lunar month in the Gregorian calendar begins on March 25th, that is, at sunset on March 24th. The 14th day of the moon is therefore on Saturday, April 7th. The following Sunday is April 8th. In the Julian calendar, the lunar month begins March 29th Gregorian, that is, at sunset on March 28th. The 14th day of the Julian lunar month is therefore April 11th Gregorian, so Julian Easter is the following Sunday. Both systems are independent of the Rabbinic calendar which placed the 14th of Nisan last year on Monday, April 18th and this year on Friday, April 6th. And all three calendars, Gregorian lunar calendar, Rabbinic calendar, and Julian lunar calendar, are 19-year metonic cycles.

On a side note the Jews devised their formula in 369 a.d. making their observance more uniform adopting the metonic cycle as well.

This attribution of the modern Rabbinic calendar to "Patriarch Hillel II" (who may not have existed, but who in any case did not devise the present-day Rabbinic calendar in all its details) is just as erroneous as the attribution of the final form of the Julian computus to the Council of Nicea. In fact the Rabbinic calendar developed over many centuries. It has been the same as today's since the 9th century A.D., but the details were still being worked out as late as the redaction of the Babylonian Talmud c. A.D. 600.

The Fathers and the canons speak for themselves.

Indeed they do, both in what they say and in what they do not say. None of the canons of Nicea mention computus at all. Constantine's letter mentions only the matters of unanimity and calendrical independence, though the reference to Passover "twice in one year" may refer to the matter of the equinox. The so-called Apostolic Canon 7 mentions explicitly only the matter of the equinox (and, implicitly, calendrical independence). Antioch Canon 1 mentions only the matters of unanimity and independence. The number 19 occurs in neither the Antiochene nor in the so-called Apostolic canon.

I know of no one who was alive at the time of Nicea and whose writings survive who writes as if the computus had been been fixed in all its details by the council, and that the details are the same as those of the present-day Julian computus. Instead, the computus appears to have remained a work-in-progress for generations. Epiphanius, in writing about the Audians, writes about the equinox, independence, and unity, but not about a 19-year cycle. The Eastern bishops at the Council of Sardica proposed a 30-year Paschal cycle. If Nicea had been considered the last word on the matter, the question need not have come up at Sardica at all. St. Athanasius appears to have been pragmatic enough to depart from the 19-year cycle he had inherited from his predecessors, even allowing Easter to fall on the 14th day of the moon in A.D. 333, changing the Easter date for A.D 346 from March 23 to March 30 in accordance with "the synod", presumably Sardica, and changing the epact (the age of the moon on a certain date) for A.D. 343 and every 19th year thereafter. And a further adjustment to the Alexandrian computus was made, apparently in the later 4th century, a change in another of the epacts. The Armenian church never accepted this last adjustment, so that Armenian Easter differs from Greek Easter 4 times in 532 years. (Though the last time this happened, in 1824, the Armenian Church, in Jerusalem at least, agreed to accept the Greek date.) If all the mathematical details of the computus had been fixed at Nicea, this last adjustment could not have been made.

I stand by my reading of history until new data arrive that clearly show another interpretation to be better.

 

[buzuxi02]

If we are to take only the most earliest sources that reference what Nicea decreed concerning Pascha, then we should disregard it altogether as obselete. Those earliest sources written by attendees of Nicea, only say that it was convened to get the asia minor churches to celebrate Pascha on a sunday after passover, rather than their own ancient custom which was to celebrate it on the day of unleavened bread relying on the jewish community. St Athanasius & Eusebius of Ceasaria, only say that these christians were the reason Nicea took up the easter question, and this reveals the context of why Constantine said to disregard the jewish calendar (as this was imperative for the quartodecimans).

I'm going to try to gather as much Patristic testimony for the first 100 years after Nicea, concerning what those Fathers claimed the Nicene Synod decreed about Pascha and post them on a seperate thread. This will atleast dispel some modern assumptions thats constantly reiterated.