Blue Christmas, also known as the Longest Night in the Western Christian tradition, is a day in the Advent season marking the longest night of the year.
On this day, some Western Christian churches hold a church service to honour people who have lost loved ones. It often includes expressing grief and heartbreak as well as an opportunity to focus on the promise of hope found in Christ.
The day draws convergence with the traditional feast day for Saint Thomas the Apostle, who struggled to believe in Jesus' resurrection. Candles, arranged as an Advent wreath, are lit during the service, and empty chairs are reserved as a way of commemorating those lost during the previous year.
Both the traditional and the more modern versions of blue holidays are based on the idea that we should all try to be more compassionate. The holiday encourages us to support those who experience sadness during the holiday season.
The worship service for Blue Christmas is traditionally held on or around the longest night of the year, which falls on or about December 21 i.e. the Winter Solstice.