JdeBP

The 1750 #UKLaw rule for calculating the date of #Easter breaks down quite simply.

The New Testament account is that Jesus rose from the dead on the day after the Sabbath, i.e. the Sunday (the Sabbath being Saturday), that followed Passover.

So what's the date of #Passover? It's the fourteenth day of Nisan, which is the first (ecclesiastical) month of the Hebrew luni-solar calendar.

Hebrew calendar months (nominally) begin at the new moon, so the 14th day is (approximately) the time of the full moon.

So when does #Nisan start? It has all been done with tables for about 16 centuries, but the underlying aim was to tie it to the vernal equinox.

Hence expressing all of this with the religions taken out: Easter is the first Sunday after the first full moon after the vernal equinox.

And because the Gregorian Calendar aimed to stabilize the dates of the equinoxes, taking even some of the #astronomy out of the rule gets this last part turned into "after the 21st of March".

#Pascha

3:57pmWeb
Show threadJdeBP6h ago

If you go and read the Calendar (New Style) Act 1750, you'll find that there the "moon" is not an astronomical one. As mentioned, the Hebrew calendar began using lookup tables about 16 centuries ago. It had all been tables for centuries by 1750.

The 1750 Act laid out tables for calculating, using a system of 'Dominical letters' and 'Golden numbers', the date of Easter.

Basically, there's a notional 'full moon' here that is calculated, not observed by looking at Luna. Hence how the drafters of the Act were able to construct tables that went up to the year 2199.

https://legislation.gov.uk/apgb/Geo2/24/23/section/6

#Passover #Pascha #Nisan #astronomy #UKLaw #Easter

Calendar (New Style) Act 1750

An Act for regulating the Commencement of the Year, and for correcting the Calendar now in use.

Show threadDaphne Preston-Kendal6h ago
@JdeBP fifteenth, not fourteenth
Show threadJdeBP5h ago

@dpk

No. The #UKLaw here is a Christian one; and Christianity bases things off 14 #Nisan.

I'm glossing over a lot because of post limitations, but there was a lot of variance over exactly how much to use of the Hebrew reckoning, as well as the Council of Nicaea.

There's also the difficulty that comes from the NT account in John having the Last Supper occurring on 14 Nisan, but that also definitely being Jesus celebrating #Pascha according to the other gospels.

Indeed, there was a whole 'Quartodeciman' thing in the early Christian church based upon people equating #Easter with (Christian) #Passover itself rather than the Sunday after it. The name 'Quartodeciman' comes from the Latin for 14th.

Basically, Christianity and Judaism do not exactly line up, when it comes to these, and have not for a long time. And Christianity has even had to theorize a pre-exilic Hebrew calendar that ran 1 day ahead to reconcile its gospels and the whole 'three days' thing.

#astronomy #GoodFriday

Show threadDaphne Preston-Kendal4h ago
@JdeBP Thank you for churchsplaining that all to me, but the claim you made in your original toot is that Passover begins on 14 Nisan, which is not the case no matter how you try to square it. The 15th begins on the day (reckoned midnight to midnight) whose majority falls on the 14th (because it is actually reckoned sunset to sunset), but it is the 15th nonetheless