Every year, before planning a vacation, buying flights or booking accommodation, we look at the calendar to find out what holidays we have. Everyone is very clear about the dates that are fixed, such as Sant Joan (June 24) or Christmas (December 25), but why does Holy Week fall, every year, on different dates?
Holy Week is linked to the lunar calendar. To set this holiday you have to follow a more or less simple rule: you have to look at when the first Sunday is after the first full moon after the spring equinox. This day will be Easter Sunday, according to Christianity, the day of the resurrection of Jesus Christ. This year that day falls on March 31.
The particularity of everything is that we are not talking about the astronomical full moon, but rather it is a 'fictitious full moon' defined by the Church through numerical tables. This full moon always occurs after March 21. Therefore, according to this rule, Easter Sunday can never be before March 22 or after April 25.
For the first three centuries after the death of Jesus, Holy Week was the only celebration of Christianity. However, among the different Christian groups and communities, there was no clear consensus on when this holiday should be celebrated. Starting in the 4th century, they wanted to put an end to the confusion.
At the First Council of Nicea, in the year 325, some conditions were established that had to be met to celebrate the Christian Easter. Among these requirements, it was stipulated that only one Easter could be celebrated a year and that it had to be celebrated on a Sunday. In addition, they also wanted to avoid it coinciding with the Jewish Passover.
