The Lutheran Calendar of Saints is a listing which details the primary annual festivals and events that are celebrated liturgically by the Lutheran Church. The calendar of the Evangelical Lutheran Church in America (and largely the one given below) is from Evangelical Lutheran Worship published in 2006 as a replacement for the 1978 Lutheran Book of Worship. The elements of the calendar unique to the Lutheran Church - Missouri Synod are from the Lutheran Service Book.
The Lutheran calendar operates on two different cycles, that of Christmas and that of Easter. Within these two cycles all events to be commemorated fall. Because Easter varies in date each year based on the vernal equinox and the phases of the moon, it is called a moveable feast (see: date of Easter). Dates affected by placement of Easter include the Baptism of our Lord, Ash Wednesday and the start of Lent, the start of Easter itself, Pentecost, and Holy Trinity. Advent, the other moveable season on the calendar, comes exactly four Sundays before the start of Christmas (if Christmas falls on a Sunday, that day does not count), or the Sunday closest to St. Andrew’s Day (November 30). Like the other Western Church calendars, the first Sunday of Advent is also the first day of the liturgical year. The events commemorated on the Lutheran calendar fall into three different categories: Festivals, Lesser Festivals, and Commemorations.