There were 52 days of the year that no one should have to labor: Sundays. For the same reason that Sundays were taken off—everyone should be free to attend Mass—there were about 40 days in the calendar that were likewise taken off because they were saints feast days or other Holy Days (Annunciation, Christmas, et cetera).
Furthermore, there were sometimes local saints in the area—not found in the official liturgical calendar established by the 12th century—whose celebrations workers were obliged to observe. These could add 20-30 additional days off to a worker. All in all, a potential 120 days—one-third of the year—could be spent in "enforced leisure." That leisure often included feasts and dances in the community. In a world without the forms of entertainment we are used to now, communal feasts and other social gatherings could be the highlights of the season.
This was not necessarily a good thing for the laborer or the employer. If he were paid by the day, he lost a lot of wages on the days when he was not supposed to work. If an employer paid by the month or the quarter, there were several days when he got no work out of his employees although they were being paid!
[For more, see Medieval Canon Law by James A. Brundage, ©1995 by Longman Group Limited]