This One’s About the Moon, and the Son


by Mike Keeler

The traditional Jewish calendar is based on the cycles of the moon. Each month has 29 or 30 days, in which the moon waxes through the first half of the month, is full in the middle of the month, and wanes until the end of the month. Works pretty well, except that after 12 months, only 354 days have passed, leaving some days left over in the solar year. If left alone, the months of the year would slip backwards about 11 days each year. To deal with this, a 13th lunar month has to be added in some years – known as “pregnant years” – to push the dates back again; out of every 19 years, 6 of them are pregnant.

The Book of Exodus tells us that the first Passover occurred under a Full Moon, in the spring. God told Moses to gather lambs, and on “the fourteenth day of the month, all the members of the community of Israel must slaughter them at twilight. Then they are to take some of the blood and put it on the sides and tops of the doorframes of the houses.” The blood allowed them to be “passed over” by the wrath of God, when He struck down the firstborn of Egypt, and released Israel from slavery. The month in question was Nisan (perhaps in 1441 BC, but don’t get us started), which is the first full month after the spring equinox.  So, for the last 3,453 years, the beginning of Passover has been celebrated on the eve of Nisan 15, under a Full Moon (and the rest of Passover flows accordingly).

The Gospels tell us that the Last Supper also occurred under a Full Moon, in the spring. Matthew, Mark and Luke all agree – though John does not – that the Last Supper was a Passover Seder. If so, it was held on the eve of Nisan 15 (perhaps in 33 AD, but don’t get us started), the Crucifixion would have taken place on that date, and the first Easter would have taken place on Nisan 17. However, when the Romans drew up the first “official” Christian calendar in 325 AD, they wanted Easter to always fall on Sunday, AND they didn’t want its date to be set in direct relation to the Jewish calendar. So, for the last 1,979 years, Easter Sunday has been celebrated on the first Sunday after the first Full Moon after the spring equinox (and the rest of the Easter calendar shifts accordingly).

Both holidays move around on our modern solar calendar, but only one also synchronizes with a day of the week. Passover can begin as early as March 21 or as late as April 20. Easter can fall between March 21 and April 25.

And so this year – as the moon would have it – Friday April 6, turned out to be doubly divine. Good Friday by day, and Passover by night.

Blood of the lamb indeed.