What is Advent? (Reblogged from here and here)
The word Advent comes from the Latin word for “arrival”: adventus. The celebration of Advent, whether with wreaths in church or calendars at home, marks the beginning of the Christmas period. It’s one of the major seasons celebrated by most Christian churches in the Western tradition: Roman Catholics, Anglicans, Episcopalians, Lutherans, and many additional Protestant churches mark the roughly month-long period with special observance.
Most Advent calendars start on December 1st, but the actual first day of the Advent season changes every year. In 2022, that day is Sunday November 27th. The final day is the same every year: December 24th, Christmas Eve — though many calendars run through Christmas Day.
The reason for the shifting start date is somewhat straightforward: as celebrated by Christian churches in the Western tradition (as opposed to Eastern Orthodox churches, which keep a different calendar), the season of Advent begins on the fourth Sunday before Christmas and is celebrated on each successive Sunday leading up to Christmas.
Once Advent finishes, the 12 days of Christmas start... It is the period that in Christian theology marks the span between the birth of Christ and the coming of the Magi, the three wise men. It begins on December 25 (Christmas) and runs through January 6th (the Epiphany, sometimes also called Three Kings' Day).