Feast of the Annunciation
The Feast of the Annunciation marks the visit of the angel Gabriel to the Virgin Mary, during which he told her that she would be the mother of Jesus Christ, the Son of God. It is celebrated on 25 March each year. It is a principal Marian feast. Two examples that highlight the importance of this feast are the first joyful mystery of the Rosary and the Angelus.
Here is recorded the "angelic salutation" of Gabriel to Mary, 'Hail, full of grace, the Lord is with thee" (Ave, gratia plena, Dominus tecum - Lk 1:28), and Mary's response to God's will, "Let it be done to me according to thy word" (fiat mihi secundum verbum tuum) (v. 38) This "angelic salutation" is the origin of the "Hail Mary" prayer of the Rosary and the Angelus (the second part of the prayer comes from the words of salutation of Elizabeth to Mary at the Visitation).
Now recognized as a solemnity, the feast of the Annunciation goes back to the fourth or fifth century.The first certain mentions of the feast are in a canon, of the Council of Toledo (656), where it is described as celebrated throughout the church, and another of the Council of Constantinople "in Trullo" (692), forbidding the celebration of any festivals during Lent, excepting the Lord's Day (Sunday) and the Feast of the Annunciation. A Synod of Worcester, England (1240), forbade all servile work on this feast day. As this feast celebrates the Incarnation of the Second Person of the Trinity, it was discussed by many of the Church fathers, to explain it to the faithful. Some of the Church fathers who wrote on this were St. Athanasius, St. Gregory of Nyssa and St. Augustine.
In the Catholic Church, Anglican, and Lutheran liturgical calendars, the feast is moved if necessary to prevent it from falling during Holy Week or Easter Week or on a Sunday. To avoid a Sunday before Holy Week, the next day (March 26) would be observed instead. In years such as 2005 when March 25 falls during Holy Week or Easter Week, the Annunciation is moved to the Monday after the Octave of Easter, the Sunday after Easter. 
The Eastern churches (Eastern Orthodox, Oriental and Eastern Catholic) do not move the feast of the Annunciation under any circumstance. They have special combined liturgies for those years when the Annunciation coincides with another feast. In these churches, even on Good Friday a Divine Liturgy is celebrated when it coincides with the Annunciation. One of the most frequent accusations brought against New Calendarism is the fact that in the New Calendar churches (which celebrate the Annunciation according to the New Calendar, but Easter according to the Old Calendar), these special Liturgies can never be celebrated any more, since the Annunciation is always long before Holy Week on the New Calendar. The Old Calendarists believe that this impoverishes the liturgical and spiritual life of the Church.
The date is close to the vernal equinox, as Christmas is to the winter solstice; because of this the Annunciation and Christmas were two of the four "Quarter days" in medieval and early modern England, which marked the divisions of the fiscal year (the other two were Midsummer Day, or the Nativity of St. John the Baptist—June 24—and Michaelmas, the feast day of St. Michael, on September 29).
When the calendar system of Anno Domini was first introduced by Dionysius Exiguus in AD 525, he assigned the beginning of the new year to March 25, since according to Catholic theology, the era of grace began with the Incarnation of Christ.
- "The Feast of the Annunciation", BBC -Religions
- Feast of the Annunciation at EWTN
- CNA, Solemity of the Annunciation of the Lord'
- Holy Family Sisters, Annunciation of the Lord
- Foley O.F.M., Leonard. "Solemnity of the Annunciation of the Lord", Saint of the Day, Lives, Lessons, and Feast, (revised by Pat McCloskey O.F.M.), Franciscan Media
- Holweck, Frederick. "The Feast of the Annunciation." The Catholic Encyclopedia. Vol. 1. New York: Robert Appleton Company, 1907. 19 Aug. 2014
|Wikisource has the text of the 1913 Catholic Encyclopedia article The Feast of the Annunciation.|