Lent and Advent seem to have a lot in common: they both have violet as their liturgical color and they are both seasons in preparation for celebrations.
So, since we all know Lent is a penitential season, is Advent one, too?
Though it’s commonly believed that Advent is a penitential season, the answer is actually no, it’s not.
The Code of Canon Law is very straight forward about what the penitential periods of the Church are:
“The penitential days and times in the universal Church are every Friday of the whole year and the season of Lent.” (CCC 1250)
So that’s it: Fridays (all year long, by the way) and Lent. Advent is not listed.
Instead, according to the General Norms for the Liturgical Year and the Calendar, Advent is “a period for devout and joyful expectation.”
So then why is Advent commonly believed to be penitential? Because it’s used to be a penitential season like Lent.
According to the old Catholic Encyclopedia, Advent originated as a 40 day fast (like Lent) in preparation for Christmas in around the fifth century. This explains the purpose of Laetare Sunday, which uses rose as its liturgical color: it was meant to be a time of respite in the middle of a long period of fasting.
But this was slowly reduced over time: by the 9th century it was reduced to four weeks, and by the 12th century the fasting was replaced by simply abstinence. The penitential character faded over time such that by at least the 20th century it was no longer considered penitential. And officially, according to Canon Law, it isn’t.