After the feast of the Circumcision (Jan. 1), the Church turns its gaze from our Lord's infancy and childhood to his public ministry, which will begin with His baptism (Matthew 3:13-17). The feast of our Lord's baptism is called the Theophany, meaning "the manifestation" or "appearance of God", and is celebrated on January 6.
During the days leading up to the Nativity, we sang the pre-festive troparion: "Bethlehem, make ready; Ephrathah, prepare youself." Beginning on January 2 at Vespers (that is, starting on the evening of January 1), we look to Galilee and the River Jordan and sing the pre-festive troparion of Theophany:
Zebulun, make ready; Naphtali, prepare yourself. O River Jordan, stand and leap for joy to receive the Master coming to be baptized. O Adam, rejoice with the first mother, Eve, and do not hide yourselves as once you did in Paradise. For, seeing you naked, Christ has appeared to put on the first robe. He has appeared to renew all creation.
Both events - the birth of Christ, and His baptism in the Jordan - were manifestations or appearances of God; in other words, theophanies. Each was a crucial step in God's plan of salvation for the human race.
The Saturday before Theophany
If one of the pre-festive days (January 2-5) falls on a Saturday, then the liturgical books appoint special readings for the day's Divine Liturgy. The Epistle (1 Timothy 3:14-4:5) contains an early statement of faith in Jesus, which emphasizes the theme of manifestation or theophany:
He was manifested in the flesh, vindicated in the Spirit; seen by the angels, preached among the Gentiles, believed in throughout the world, taken up in glory.
The Gospel (Matthew 3:1-11) describes the preaching and baptismal ministry of John the Forerunner.
The Sunday before Theophany
If one of the pre-festive days falls on a Sunday, then a special prokeimenon and alleluia are sung at the Divine Liturgy, asking God's blessing and assistance. In the Epistle (2 Timothy 4:5-8), Saint Paul refers to all those "who have looked for his appearing with eager longing." The Gospel is another account of the ministry and preaching of John the Baptist, taken this time from the very beginning of the Gospel according to Saint Mark (Mark 1:1-8).
The Royal Hours of the Theophany
Since December 25, there has been no fasting; we have kept festival in honor of our Lord's birth.
However, the Church does appoint a single day of fasting before the feast of our Lord's Theophany. Normally, this is on January 5, the "Paramoni" or "Vigil" of Theophany. However, if January 5 falls on a Saturday or Sunday - days on which we do not normally fast - then the fast day is transferred to the previous Friday.
On this day, a special service called the Royal Hours is celebrated. This service consists of the daytime services of the First Hour, Third Hour, Sixth Hour, Ninth Hour, and Typika, celebrated with special psalms and readings for the Theophany. (This service is called royal because, at one time, the Emperor himself always attended the service.) Each part of the service has an Old Testament prophecy, an Epistle reading, and a reading from the Holy Gospel.
The Vigil of the Theophany
Finally, we have come to the eve of the feast - the Paramoni or Vigil of Theophany (January 5). If it is a weekday, it is a day of strict fasting, with the Royal Hours celebrated during the day, and Vespers and the Divine Liturgy of Saint Basil in the evening.
If January 5 is a Saturday or Sunday, the Divine Liturgy may be celebrated in the morning, and we sing the troparion of the Vigil:
After Elijah has been taken up, the River Jordan was parted in two by Elisha's mantle; and a dry path was opened in the waters as an image of true baptism by which we pass beyond this fleeting life. Christ appeared at the Jordan to sanctify the waters.
By tradition, a Holy Supper (meatless but festive) is held on the evening of January 5, after Vespers, just as on Christmas Eve. We have arrived at the brink of the feast of the Theophany - the baptism of our Lord, God and Savior Jesus Christ.
Source
