Moveable Feasts move; around the calendar. In the liturgical or Christian calendar, there are several observances or events which fall on different dates every year. Easter Sunday is the most important moveable feast in Christianity and although it is always observed on a Sunday to remember the resurrection of Jesus Christ, the date varies from year to year.
There are many other observances which do not have a fixed date (collectively known as moveable feasts) in the liturgical calendar and depend on the Easter calendar.
The most significant moveable feasts are observed within a fixed number of dayspreceeding or succeeding Easter Sunday.Moveable Feasts in Eastern Christianity
The set of moveable feasts in the liturgical calendar of eastern Christianity constitutes the Paschal Cycle. Pascha is the common term used for Easter and is considered to be the original moveable feast. The dates of all the other moveable feasts observed by members of the Eastern Orthodox Church fall within a duration of approximately 10 weeks before and 7 weeks after Pascha. The Paschal Cycle can be categorized as follows:
In Western Christianity, like Eastern Christianity, the dates of the moveable feasts are set around Easter. The use of Gregorian calendar instead of Julian calendar (which is followed by the Orthodox Church) and a different Paschal Cycle (an 84-year cycle in contrast to a 19-year cycle) results in different sets of dates for the observations each year. Roughly, the Paschal Cycle for Western Christianity can be broken down as follows:
Technically, both members of Western Christianity and members of Eastern Christianity use the same calculation (i.e., a fixed period of days) for determining the dates of the moveable feasts based on the date of Easter/Pesach. However, the rules of calculation of the Easter Calendar varies between the Roman Catholic Church and the Eastern Orthodox Church as well as the system of calendar used by each.
A list of some important moveable feasts observed by Christians in different regions of the world is as follows: