Advent

Advent brings another tradition popular even with those who do not normally attend church: sing-along carol concerts, known as "The Most Beautiful Christmas Songs".

At Lutheran churches, they have been co-sponsored since 1973 by the Finnish Evangelical Lutheran Mission..

Source: http://www.yle.fi/uutiset/news/2010/11/advent_ushers_in_holiday_season_2177137.html