From the Pastor: Happy Easter
It is Easter Sunday. That means that this bulletin article was written during Holy Week. That also means that the pastor was too busy to write it. So here is a “re-run” of one of my favorite bulletin articles from years past, titled, “Do you know how to calculate the date of Easter?”
The other day I was going through the Baltimore Book of Prayers and came upon a mathematical method for computing the date for Easter. I have to admit that I had never put much thought into this particular aspect of computing the Easter date. I had known there was something about Easter falling on the first Sunday after the first Tuesday following the first full moon after the spring equinox. Or something like that. Or perhaps there was something about the Paschal full moon instead of the astronomical full moon. Of course, because of different time zones in various parts of the world I never knew exactly where the moment of the full moon was calculated. Was it in Jerusalem? Rome? San Antonio? But I am rambling...
Regardless of exactly how the date was set or where it was set, it only makes sense that there is a mathematical method of calculation to find it. After all, calendars and all they contain are mathematical. New Years, number of days per month, high tides, sunset and sundown, moon phases, eclipses and other such occurrences are determined not by simply watching and observing but can be “predicted” in advance due to calculations based on the Earth’s rotation, the speed of the planets revolving around the sun and other known factors which require mathematics. The whole universe is laid out logically and logics is a science within mathematics. Or is it that mathematics is a science within logic? So there is a formula for calculating the upcoming (and past) dates for Easter.
No, I am not yet ready to tell you what it is. Before that I have to admit how pathetic it is that I have to check the calendar to know when Easter falls. According to the Catholic Encyclopedia “The computus paschalis, the method of determining the date of Easter and the dependent feasts, was of old considered so important that Durandus (Rit. div. off., 8, c.i.) declares a priest unworthy of the name who does not know the computus paschalis.” Yes, I am an unworthy priest. Mea culpa. And now for the moment you have all been waiting for (drum roll, please!)...
Straight from the Baltimore Book of Prayers, pages 19 and 20, “A Rule for Finding Easter of any Year in This Century or the Next.” Ooops, I cannot get to it quite yet. “This century” was the 19th, for that is when the book was published, “or the Next” was last century. Which means that I cannot verify without a little mathematical work (which I am not willing to do and perhaps not even capable of doing, but we will never know) if this formula holds true for this century or if it needs to be tweaked each century. Now back to the formula.
1st. Divide the date of the year by 19, and call the remainder a;
2d. divide the date of the year by 4, and call the remainder b;
3d. Divide the date of the year by 7, and call the remainder c;
4th. Divide 19a [for this century; + 24 for the next] by 30, and call the remainder d;
5th. Divide 2b + 4c + 6d + [5, this century; 6, next century] by 7, and call the remainder e;
Then Easter will be the 22d + d + e of March; or the d + e - 9 of April.
Exceptions-- 1st. When Easter would fall on April 26th, put it back to the 19th.
2d. When it would fall on April 25th, put it back to the 18th, if a is more than 10, and d is 28.
I sure hope this helps you understand the easy way to calculate the date we celebrate Easter, from which we then calculate many other feasts. That is, unless you happen to follow the Orthodox and perhaps some Eastern Catholic liturgical calendars, in which case the Easter date is sometimes the same and sometimes different.
With prayers for your holiness,
Fr. Edwin Palka