How is Easter determined?

It seems so late this year — Easter. How does that happen?

The date for Easter is determined by a few astrological happenings: the   Spring Equinox, Passover, and the Full Moon. I guess you could say we’ve become rigid in our understanding of dates since we follow the Gregorian calendar — we no longer look at the moon to determine the date. But, the Jewish calendar is based on the moon — thus a lunar calendar. The moon determines when we celebrate Easter — it falls on the first Sunday, after the first full moon after the spring equinox.

And this is how we got there:

The Bible indicates that Christ died and was resurrected around the time of the Passover, which falls on the full moon after the spring equinox.

When the hour came, Jesus and his apostles reclined at the table. And he said to them, “I have eagerly desired to eat this Passover with you before I suffer. For I tell you, I will not eat it again until it finds fulfillment in the kingdom of God. (Luke 22: 14)

This led Christians to celebrate Christ’s resurrection at the same time as Passover. By the end of the 2nd century, some churches celebrated on Passover, and others on the Sunday following Passover. So however you want to look at it — Easter falls on the Sunday following the first full moon after the spring equinox or you could say that Easter falls on the Sunday following the first night of Passover. Since Passover is always on the first full moon after the Spring equinox.

These are the appointed times of the LORD, holy convocations which you shall proclaim at the times appointed for them. In the first month, on the fourteenth day of the month at twilight is the LORD’S Passover. ‘Then on the fifteenth day of the same month there is the Feast of Unleavened Bread to the LORD; for seven days you shall eat unleavened bread.…(Leviticus 23:4-6)

In 325 CE, the Nicene Council ruled that Easter would fall on the first Sunday after the first full moon after the spring equinox.  If the full moon falls on a Sunday, Easter is the following Sunday. Therefore,  Easter falls on a Sunday sometime between March 22 and April 25 from 1753 to 2400.

When Jesus died, Passover fell close to the Jewish Sabbath day,

Now there was a man named Joseph, a member of the Council, a good and upright man, who had not consented to their decision and action. He came from the Judean town of Arimathea, and he himself was waiting for the kingdom of God. Going to Pilate, he asked for Jesus’ body. Then he took it down, wrapped it in linen cloth and placed it in a tomb cut in the rock, one in which no one had yet been laid. It was Preparation Day, and the Sabbath was about to begin.

The women who had come with Jesus from Galilee followed Joseph and saw the tomb and how his body was laid in it. Then they went home and prepared spices and perfumes. But they rested on the Sabbath in obedience to the commandment.(Luke 23: 50-56)

So, for example for 2019:

Spring Equinox: March 20, 2019

Full Moons: March 20, 2019 (supermoon) April 19, 2019 (fullmoon)

Passover: begins April 19, 2019  at sundown

Easter: Sunday, April 21,2019