Easter is called a movable feast because the date of Easter changes every year. Easter Sunday can fall on any date from 22 March to 25 April.
The reason for this variation in the date of Easter is based on the lunar calendar (moon) rather than our more well-known solar one.
Easter always falls on the first Sunday following the full Moon (the Paschal Full Moon) after 21 March. If the Full Moon falls on a Sunday then Easter is the next Sunday.
Why Does Easter Change Dates? Why does the date of Easter move?
Here’s What You Should Know About the Religious Holiday
While Easter sometimes falls later in the year, so those celebrating with family and friends and gathering for Easter meals will do so much earlier that they might have in years past (weeks earlier when compared with 2019!). Of course, this also means that the beginning of Lent and Ash Wednesday occur earlier, too.
The varied dates from year to year can leave many people wondering why Easter changes dates instead of remaining the same. Most Christians know Ash Wednesday’s date depends on Easter, but wouldn’t it be much simpler (and easier to remember) if Jesus Christ’s resurrection were celebrated on a set day, the way holidays like Christmas and Valentine’s Day are observed? Here’s a look at why that’s not the case.
Ash Wednesday signals the period of 40 days before Easter, called Lent, when observants typically “give up” some earthly pleasure (wine, chocolate) as a form of penance. But what does Ash Wednesday mean?
The holiday stems from the Old Testament book of Daniel that associated fasting with ashes, according to priest and Duke Divinity School assistant professor Lauren F. Winner. Its main ritual involves a priest invoking Genesis 3:19 (“for you are dust, and to dust you shall return”) while anointing congregants’ foreheads with a mix of ash from Palm Sunday — itself derived from the story of Christ’s route to Jerusalem being padded by palm fronds—and sometimes oil. Lent is an acknowledgment of the 40 days the Bible says Christ spent in the wilderness.
Because Ash Wednesday kicks off the Lenten season, its date is always exactly 46 days before Easter (40 days of Lent, plus six, as each Sunday is skipped) and thus is affected directly by what date Easter falls on that year.
Which brings us to our central question: Why is Easter on a different date each year? The holiday, which celebrates Christ’s return from the grave following his crucifixion, can occur on any Sunday between March 22 and April 25. (That’s a pretty big range!)
Easter’s exact date varies so much because it actually depends on the moon. The holiday is set to coincide with the first Sunday after the Paschal Full Moon, the first full moon after the vernal equinox. Though the equinox’s exact date can vary each year according to the Old Farmer’s Almanac, the church always recognizes the vernal equinox as March 21.
So why does Easter come after the Paschal Full Moon? Early Christians wanted Easter to coincide with Passover, because Christ’s death and resurrection happened after the Jewish holiday, writes Christian minister Mary Fairchild. Because the Jewish calendar is tied to solar and lunar cycles, the dates of Passover and Easter fluctuate each year.