Tomorrow is Christmas Eve
Why will we begin our Christmas celebrations tomorrow evening? A Liturgical Eve is the evening or day before a feast or other important celebration. Depending on local customs and practice, the celebration of a feast may begin on the eve of the feast. In many parishes, the principal Christmas services take place on Christmas Eve.
Christmas celebrations in the denominations of Western Christianity have long begun on Christmas Eve, due in part to the Christian liturgical day starting at sunset, a practice inherited from Jewish tradition and based on the story of Creation in the Book of Genesis: "And there was evening, and there was morning – the first day." So, in Jewish and Christian tradition, the day begins at sunset and continues until the following sunset, and not as we usually think of as midnight to midnight.
The Book of Common Prayer provides directions for a Vigil of Pentecost (pp. 175, 227). The Book of Occasional Services provides forms for a Vigil for Christmas Eve, a Service for New Year's Eve (Eve of the Feast of the Holy Name), a Vigil for the Eve of All Saints' Day or the Sunday after All Saints' Day, a Service for All Hallows' Eve (Oct. 31), and a Vigil on the Eve of Baptism.*
*Source - An Episcopal Dictionary of the Church, https://www.episcopalchurch.org/glossary/eve-liturgical/ and Wikipedia, https://en.wikipedia.org/wiki/Christmas_Eve
Let us pray.
O God, our times are in your hand: Look with favor, we pray, on your servants as we celebrate another Christmas. Grant that we may grow in wisdom and grace, and strengthen our trust in your goodness all the days of our life; through Jesus Christ our Lord. Amen.✢
✢BCP, page 830, adapted