Epiphany is the end of the Christmas season. It's sometimes called Twelfth Day (hence Twelfth Night the evening before) because it's the twelfth day from Christmas. The famous Twelve Days of Christmas are those from Christmas to Epiphany. They include the Feast of the Innocents (commemorating the slaughter by Herod of the children), the Feast of the Circumcision (commemorating Jesus' parents keeping the law by having him circumcised on the eighth day), and the Feast of Stephen (commemorating the first martyr).
Epiphany itself began in the very early Eastern church as a nativity celebration but by the middle ages it became, in the Western church especially, a declaration of the manifestation of Christ to the nations as the Hope of the Nations. The Magi were Gentiles, and thus represented the nations, and so in Christian story they became kings, who are heads of their people, because of all the prophecies of kings bringing their kingdoms to the Messiah: "kings will walk in the brightness of thy rising."
So Epiphany is a glorious celebration of the King of the Nations, the Ruler of the World, the Eternal Augustus, the Everlasting Princeps, whose empire has no end in time or space. When we pray "Thy kingdom come", we should remember that Christians have already been praying that for two thousand years and the answer to that prayer was immediate (Already) and is still growing (Not Yet). In his birth, life, death, and resurrection, Jesus Christ triumphed (past tense) over his enemies, and He will reign till He has put all His enemies under His feet, and that will indeed happen. He wins, they lose. Epiphany is a wonderful time to remind ourselves that that phrase in the Lord's Prayer MEANS SOMETHING. This is 2007 A.D. -- In the Year of the Reign of Our Lord and King Jesus Christ. He owns the world.
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