"Entia non sunt multiplicanda praeter necessitatem." - William of Ockham ("Occam's Razor": among competing solutions, select the one that makes the fewest assumptions)
"Never attribute to malice that which is adequately explained by stupidity." - Robert J. Hanlon ("Hanlon's Razor")
To all my Christian friends: Happy Easter!!!!
To all my friends who don't practice Christianity: Happy Easter to you, too!!!!
Which brings us to the question of why in the heck Easter bumps around the calendar so much, doesn't it? Well, it brings me there, anyway, and I'm'a takin' you along for the ride, with your gentle permission.
I have, over the years, fallen into and out of the practice of a fair variety of religious/spiritual faiths. I'm pretty firm now in my beliefs (and no, they're not spelled out in my Return of the Gods works of fiction), but while I was younger I went through all sorts of experimentation. Never had intercourse on an altar table like a certain candidate for the Senate claimed to, but yeah, I shopped around.
During that experimentation I happened upon the theory that Easter is scheduled on the date it is because the early Church wanted to squish out paganism. In doing so, they named and timed their major holidays to coincide with pagan ones, in this case the spring celebration of the pagan goddess Eostre, whose symbols (as a goddess of fertility/spring) were of course the bunny and the egg.
Darn those Christians. Darn them to heck.
Now, for much of my life prior to this period I was a fairly devout Methodist, to the point where you'd see me carrying a Book of Discipline around with my KJV Bible w/ Concordance. As much as I'd studied church lore, then, and as much as I loved spouting off with Hanlon's Razor, you'd think I wouldn't have gone for the "Church Ate My Holiday" conspiracy theory.
But I did.
I've learned more since, though.
It turns out that Hanlon's Razor is particularly appropriate in the explanation for the timing of Easter. In the early days of the church, there wasn't even a standardized calendar. As the faith spread through the western hemisphere, those in Europe followed the Julian, solar(ish), calendar, while those elsewhere followed the Hebrew, lunar(ish), calendar. Easter, the holiday celebrating the rise of the Christian church's lord and savior, was thus celebrated on all sorts of days, often as not tied to the Jewish celebration of Passover.
That last fact really irked many, particularly western, Christians in the first couple of centuries, by the way. They still blamed the Jews for killing Christ, after all. Why, then, should they let the Jews tell them when to celebrate His resurrection?
Enter, Stage Right, that most inefficient of all human creations, the group. You know, that organization that bequeathed upon the United States our three-fifths compromise? Yeah, same thing, same stupidity, many centuries earlier. In this case, in 325 AD, the new Roman Emperor, Constantine I, decided he needed to call everybody together to get some things straight. So he called them all to a spot that was geographically central: the city of Nicaea, which was a large settlement at the time. These days it's known as Iznik, Turkey, and wouldn't even qualify, population-wise, for its own Wal-Mart, not that that detail is particularly important. But if you're looking for Nicaea on the map, fuggeddaboutit.
All that said, the Emperor invited all 1,800 bishops of the church to gather in Nicaea to resolve some of the major canonical issues they were having. And when the Emperor calls, the bishops come, right? Not really. Three bishops who were there published three different counts of attendees, numbers between 220 and 318, a variance that can probably (at least sarcastically) be explained by the fact that they were counting with Roman numerals.
"Was that XXIII or XXXII? Oh, dang, now I must start over."
Socrates and others who weren't there later said there were 318 bishops in attendance, and hey, since they wasn't there, they must've had it right. Glenn Beck would've probably estimated attendance at around 10,000, based on multiple drawings of the same bishops from different angles, and since that number feels best I'll just go with it, okay?
Now, where was I? Oh, right, the Nicaean Council. So all ten thousand bishops started talking about the major philosophical divides that were plaguing the early church. Things like the divinity of Christ. The need for a standardized Creed, because if everybody isn't murmuring exactly the same thing, you can't say you have a real church, right? The need for more laws ("canons" is the correct term, I suppose) on important subjects such as the invalidity of baptisms done by the heretic Paul (not the same Paul who wrote all the bestselling letters. I suspect he went by "The Other Paul" in online social media).
Oh, and the date of Easter.
Sort of, anyway. What the First Council of Nicaea (yeah, it worked so well they had another one a few hundred years later) did, specifically, was rule that Easter/Pascha would no longer be timed according to the Jewish calendar, and also that it would take place on the same day world-wide.
What they did was leave the actual calculation part as an exercise for the reader, kind of like in those physics texts that nobody ever actually reads.
Note, by the way, that so far I've said Julian calendar. That was the modification of the Roman calendar done in the name of Julius Caesar. For one thing, he wanted January 1 to be in the actual winter, so he decreed as the Roman Emperor that what we now know as 46 BC would actually be 445 days long. (could you imagine having to deal with the IRS over that kind of a shift?) Also, he recalculated everything so that they'd still have the special solar/lunar-ish alignment with the parts of each month (hence the shorter and the longer months) but the year would correspond to the 365.25 days the earth takes to fully traverse its path around the sun rather than the nice, round number of 365 days the earlier Roman calendar used.
Future emperors, of course, ignored parts of what Julius had put in place, thus causing the year to wander around a bit, but that's neither here nor there to this story. The key fact is that now we use something called the Gregorian calendar, named after a Pope this time, which realizes that 365.25 is actually just a skosh off. To acknowledge the fact, Pope Gregory XIII decided (well, a Jesuit scholar decided and he signed off on it, technically) that we'd toss away one Leap Day every hundred years.
Oh--and he also made ten days disappear that year. Poof! Bye bye!
Keep in mind that the Pope is Catholic. You knew that, right? Problem was, in 1582, when Pope Gregory XIII did the deed, there were already plenty of Protestants and other non-Catholic Christians in the world who really didn't give a rat's behind what the Pope said about their calendar.
Imagine yourself back then. Your Pope says it's one month. The folks down the street have a calendar that says it's different. Now figure out when to celebrate Easter. I dare ya....
Anyway, that's basically why Easter is the date it is--the first Sunday after the first full moon after the vernal equinox is a whole lot easier to understand and calculate than all that other crap.
Luckily Christmas is always the same date every year. Wal-Mart would have a helluva time figuring out its sales cycles otherwise.