Why is Easter Sunday on a different date every year and not like Christmas which is on the same date every year. – Gerry

Dear Gerry,

A very interesting question, indeed! To understand our current practice we must go back to the early centuries of Christianity. As a way of co-opting pagan festivals, the Church would often “baptize” such celebrations, giving them a particularly Christian flavor. For example, the Romans celebrated the Birth of the Unconquered Sun. This pagan feast was celebrated on December 25th, which was considered the winter solstice, the shortest day of the year. In the 4th Century A.D. the Church took this pagan celebration and made it a celebration of the Birth of Christ, who was referred to as the Sun of Righteousness. So, this Christian celebration was celebrated on a fixed date, December 25th.

Easter is another story. The celebration of Easter is forever bound up in the celebration of the Jewish festival of Passover (ref. Gospel accounts, e.g., the Last Supper, the sacrifice of the Passover lambs, etc.). The date of Passover is determined by a more complicated procedure, based on two astronomical events: the Vernal or Spring equinox (March 21) and the next full moon. In the early Church, two practices emerged for the celebration of Easter – one, where it was celebrated on the 14th day of the Jewish month of Nisan, and the other on the next Sunday after 14 Nisan. Eventually, the second practice became established, especially because Sunday was the day of the Resurrection. So, as a rule of thumb, Easter is celebrated the first Sunday after the first full moon after the Vernal Equinox. Simple, right?

aka Fr. Ed C.Ss.R.