usr/src/usr.bin/calendar/calendars/calendar.christian

01/06*  Epiphany
02/11*  Shrove Tuesday / Mardi Gras (day before Ash Wednesday)
02/08*  Ash Wednesday (First day of Lent)
03/19*  Palm Sunday (7 days before Easter)
03/23*  Maundy Thursday (3 days before Easter)
03/24*  Good Friday (2 days before Easter)
03/26*  Easter Sunday
05/04*  Ascension Day (10 days before Pentecost)
05/14*  Pentecost (Whitsunday)
05/15*  Whitmonday
05/21*  Trinity Sunday (7 days after Pentecost)
05/25*  Corpus Christi (11 days after Pentecost)
05/28*  Rogation Sunday
10/18   Feast Day of St. Luke
12/03*  First Sunday of Advent (4th Sunday before Christmas)
12/06   St. Nicholas' Day