In my line of work, banking holidays don’t mean anything. Araw ng Kagitingan? Meh, I still have to come in to work to compute my tenants’ water bills on the 9th of every month, no exceptions. Bonifacio Day? Nope, sorry, still gotta show up since that’s the anniversary of our workplace at my day job.
Come to think of it, the only actual holidays that apply to my occupation are Christmas and Easter Sunday. The former is easy enough to plan for since it happens on a fixed day every year. Not so with Holy Week, which precedes Easter, as the dates vary every year.
This brings us to the question of why Holy Week never occurs on the same dates, and how the evangelical authorities actually decide when these literal holy days are supposed to happen.
Easter Sunday as a “Movable Feast”
The observance of Holy Week has been around for nearly half a millenium now. Since 1582, it has begun as early as March 22 and has ended as late as the last weeks of April.
Now, Easter Sunday is considered a “movable feast,” which is a term used to describe an event that doesn’t have a fixed date on the Gregorian calendar. And since Holy Week is defined as the six days preceding it, its dates too, tend to shift every year.
But why is Easter Sunday movable to begin with? It all has to do with the Resurrection story and the Jewish calendar.
If you’ll recall, the Last Supper occured on Passover, which is commemorated every Maundy Thursday. Jesus Christ was said to be resurrected from the dead three days hence. Thus, the first Easter Sunday is traditionally considered to be the Sunday after that particular Passover.
However, the dates of Jewish feasts are, you guessed it, also movable. Their liturgical calendar follows both lunar and solar cycles unlike the regular calendar, which only follows the latter. The Council of Nicaea back in 325 AD also decreed that the dates for Easter and Passover should never coincide. Given that Passover falls on the Paschal Full Moon on the Jewish calendar, the Sunday that follows is automatically considered Easter Sunday.
TLDR version: A theological council decided that Easter should be universally celebrated on a Sunday after the first vernal full moon every year.
Computus: Determining the Easter Date
Yep, there’s actually a name for the algorithm used to determine the date for Easter Sunday.
Full moons are well and good, but they can occur on different days in different time zones. In other words, if people living in different time zones were to calculate the Easter date depending on when they saw the paschal full moon, there wouldn’t be a universal date.
As a more practical solution, the church simply opts to use an approximation of the paschal full moon rather than its exact date. So, to compute for Easter Sunday, they rely on two assumptions:
The paschal full moon is always on the 14th day of the lunar month;
March 21 is typically assigned as the date of the vernal equinox (even if it can occur a day prior to or after this date).
Okay, so despite having read all that, the concept is admittedly a little tricky to wrap one’s head around. But no worries, you can always refer to this table of Holy Week dates for the coming years if you don’t want to calculate next year’s Easter date yourself.
Have a blessed Holy Week ahead!