Today that hymn is known as an "Advent hymn" It is a lyrical embellishment of a very old Gregorian chant. The chant is known as an "O Antiphon" and without getting into too much detail, the chant is recited still today during advent by many, many churches. Different parts are recited on different days leading up to Christmas day, each day focusing on a particular name of Jesus used in the Bible:
* December 17: O Sapientia (O Wisdom)
* December 18: O Adonai (O Adonai)
* December 19: O Radix Jesse (O Root of Jesse)
* December 20: O Clavis David (O Key of David)
* December 21: O Oriens (O Dayspring)
* December 22: O Rex Gentium (O King of the nations)
* December 23: O Emmanuel (O Emmanuel)
What's really neat is that if you take that list of names written in latin above and make an acrostic out of it going from bottom-to-top, you'll see that it spells the latin, "Ero Cras" which translates to "Tomorrow, I will come". Pretty neat huh?
You can thank our Roman Catholic brothers for such a rich and interesting history. Here are the lyrics of that hymn, for your consideration, keeping in mind what we talked about Wednesday night, that we are in a constant state of advent:
O come, Emmanuel,
And ransom captive Israel,
That mourns in lonely exile here
until the Son of God appear.
O come, Thou Rod of Jesse,
free thine own from Satan's tyranny;
From depths of hell Thy people save,
and give them victory over the grave.
O come, Thou Day-spring, come and cheer
our spirits by Thine advent here;
and drive away the shades of night
and pierce the clouds and bring us light!
O come, Thou Key of David, come,
and open wide our heavenly home;
make safe the way that leads on high,
and close the path to misery.
O come, Thou Lord of might,
who to Thy tribes on Sinai's height
In ancient times once gave the law
in cloud, and majesty, and awe.
