Easter Sunday is a ‘movable’ festival
- Why does the date of Easter vary from year to year?
- Easter can fall between March 22, up to the 25th Of April.
1858: “The remainder of the moveable feasts in the Church year, as well as the celebration of Ash Wednesday and Good Friday, depend upon the date of Easter, or the Festival of the Resurrection of the Saviour from the tomb. The derivation of the word Easter from a Saxon word, Oster, which means to rise, shows that the character of the day is manifest in its etymology.
Easter day was celebrated at the Paschal full moon, in consequence of the relation of the Resurrection to the Passover. Lardner tells us, that many of the early Christians held Easter to be the Jewish Passover continued as a Christian rite, and celebrated it on the day of the Passover, instead of the Sunday after. The Nicene Council put a stop to this notion and practice; and means were taken at the Reformation of the Calendar to prevent the Christian festival from falling actually upon the same day as that of the Jewish Passover.”
In forming the law for the fixing of Easter, two things had to be kept especially in view; first, the fact of the occurrence of the Resurrection about the Vernal Equinox, and second, that it was after a full moon. With these facts the idea was quickly obtained that the festival should be celebrated on the Sunday which next succeeded the first full moon after the 21st of March, and in case “the full moon happens upon a Sunday, Easter day is the Sunday after.”
From this law we shall see that the earliest day on which Easter could fall would be the 22nd of March, and that this would only occur when the full moon appeared on the 21st of the month, the day of appearance being Saturday. The latest period for the festival is the 25th of April, which occurs when the full moon happens on the 20th of March. This moon is not then considered the Paschal moon, as it is before the Vernal Equinox, and the true Paschal full moon will really occur on the 18th of April. Should this day be Sunday, according to the general law, Easter will be the next Sunday, which would be the 25th.
Easter day has fallen on the 22nd of March, in 1598, 1693, 1761, 1818, and will occur on that day in 2285. It has been celebrated on the 25th of April in 1666, 1734, and will be on that day in the years 1886, 1943, 2038 and 2190. Between these two periods,—a space of thirty-five days—Easter may happen in accordance with the conditions first named, and as it controls most of the moveable festivals, their position in the Church Calendar may vary within the same limits, i.e., thirty-five days.
It would be erroneous to conclude from what has been stated as the law for determining Easter, that the Astronomical moon has any thing to do with it at the present day. Many changes have taken place in the science of Astronomy, since Easter day was fixed by the Church. Ideas about the movements of the Sun and Moon, then prevalent, have been rejected. This rejection would necessarily affect, more or less, the determination of Easter, but in order to preserve the old law, an ecclesiastical, or conventional moon has been created, by the age of which Easter is regulated.
Easter is in fact determined by finding the first Sunday that succeeds the 14th day of the first ecclesiastical moon which occurs after the 21st of March, and if this 14th day occurs on Sunday, the Easter festival is celebrated on the next Sunday. In order to show that there is a difference between the Sundays which would be selected as Easter by the astronomical and the ecclesiastical moon, two cases from Arago may be cited.
In 1798, Easter according to the astronomical moon should have been on April 1st, but, in fact being regulated by the hypothetic moon, it occurred on the 8th. In 1818, the day was determined astronomically as the 29th of March, but was celebrated in accordance with the ecclesiastical moon’s indication on the 22nd. The reason why the determination is not made by the actual moon, consists simply in the fact that its position is obtained from astronomical tables, which are yearly being altered, as the science becomes more perfect.
These tables are not constructed for many years in advance, and the Church would thus be dependent for the fixing of Easter on the appearance of the Civil Calendar. Whereas, according to the present system, tables are furnished us of the days, on which Easter will fall, for centuries to come“.—The Calendar; 1858.
1903: “Easter varies from year to year because it is one of the movable feasts of the Christian Church. The proper time for its celebration has caused much controversy. In deference to ancient custom, ecclesiastical authorities, at the time of the introduction of the Gregorian calendar, decided to adhere to the method of Easter’s determination by the moon.
This is not the actual moon in the heavens, but an imaginary moon whose periods are so contrived that the calendar moon always follows the real new moon by two or three days. Easter Day is always the first Sunday after the paschal full moon, i.e., the full moon which happens upon or next after the 21st of March (the beginning of the ecclesiastical year); and if the full moon happens upon a Sunday, Easter Day is the Sunday following.”—Current Literature; Jan-June; 1903.
For those of us who would prefer a simple source for determining when Easter is… Here’s a good link for future reference!