Therefore the Lord himself shall give you a sign; Behold, a virgin shall conceive, and bear a son, and shall call his name Immanuel.”Isaiah 7:14 (KJV)
The roots of the music of Oh Come, Oh Come, Emmanuel! go back to the 15th century.1 The Messianic titles in the lyrics, called the O Antiphons, are from the Old Testament, and their use in liturgy goes back to the 8th century.2
The first letters of the titles taken backwards form a Latin acrostic of “Ero Cras” which translates to “Tomorrow, I will come”, mirroring the theme of the antiphons.3
O Sapientia (O Wisdom)
O Adonai (O Lord)
O Radix Jesse (O Root of Jesse)
O Clavis David (O Key of David)
O Oriens (O Dayspring)
O Rex Gentium (O King of the nations)
O Emmanuel (O God is with Us)
Start with Emmanuel and go backwards through the Latin names, taking the first letter of each to obtain the phrase, Ero Cras.
Oh Come, Oh Come, Emmanuel! is one of the oldest songs heard during the Advent season. This video features an anonymous cornet soloist from Trefor, Wales.
God, after He spoke long ago to the fathers in the prophets in many portions and in many ways, in these last days has spoken to us in His Son…Hebrews 1:1-2
In the December 2010 Jews for Jesus newsletter, Ceil Rosen described singing in a high school chorus Christmas program that included Oh Come, Oh Come, Emmanuel! She wrote, “Though we had rehearsed those words many times, I suddenly found myself pondering their meaning. Was there something true about Jesus being for us Jews?” This is her story as she told it in 1977: Then I Met Messiah.
“Rejoice! Rejoice! Emmanuel shall come to thee, O Israel….”
Alternate lyrics: Lutheran Worship hymnal, ECUSA 1871.
1O come, O come, Emmanuel, Tunes: Veni Emmanuel, Hymnary.org
2, 3O antiphons: Wikipedia.