Not only do the readings for the daily Masses just before Christmas include the beginnings of the Gospel infancy narratives (Matthew 1 on Dec. 17-18; Luke 1 on Dec. 19-24), but we again get to hear the traditional “O Antiphons,” at Mass. Most of us were introduced to the antiphons via the popular hymn, “O Come, O Come, Emmanuel.” Yet the “O Antiphons” are more than a thousand years old.  Curiously, the first verse of the familiar hymn is actually the last of the traditional “O Antiphons” while the other verses of the hymn (in the order printed in most hymnals) correspond to the Antiphons for Dec. 17 to 22:

Dec. 17: O Sapientia / O Wisdom                           from Evening Prayer
Verse 2: O Come, Thou Wisdom, from on high       from the popular hymn

Dec. 18: O Adonai / O Sacred Lord of ancient Israel
Verse 3: O Come, O Come, Thou Lord of might

Dec. 19: O Radix Jesse / O Flower of Jesse’s stem
Verse 4: O Come, Thou Rod of Jesse’s stem

Dec. 20: O Clavis David / O Key of David
Verse 5: O Come, Thou Key of David, come

Dec. 21: O Oriens / O Radiant Dawn
Verse 6: O Come, Thou Dayspring from on high

Dec. 22: O Rex Gentium / O King of all the nations
Verse 7: O Come, Desire of nations…

Dec. 23: O Emmanuel / O Emmanuel
Verse 1: O Come, O Come, Emmanuel

The importance of the “O Antiphons” is twofold. First, each one is a title for the Messiah. Secondly, each one refers to the prophecy of Isaiah of the coming of the Messiah.

Also interesting is that the first letters of the titles, from last to first, appear to form a Latin acrostic, ‘Ero cras’, meaning ‘Tomorrow, I will be [there]’, mirroring the theme of the antiphons. This is formed from the first letter of each title – Emmanuel, Rex, Oriens, Clavis, Radix, Adonai, Sapientia. Such acrostics were popular among early medieval writers, and some scholars have taken this as further evidence for their antiquity.