The "O Antiphons"

Although baptised in the True Church and catechised through first Confession and Communion, I was yanked from Catholicism at an early age and have found a great many holes in my spiritual knowledge since beginning to return to Rome in 1998. One of the things I haven't known about until the last few years has been the "O Antiphons" of Advent, and I am joyfully paying close attention to them this year. The title above links to Fr. Z's excellent explanation of this beautiful liturgical tradition.

For 20 December :

O Clavis David

LATIN:
O clavis David, et sceptrum domus Israel: qui aperis, et nemo claudit; claudis, et nemo aperit: veni, et educ vinctum de domo carceris, sedentem in tenebris.

ENGLISH:
O Key of David, and scepter of the house of Israel, who opens and no man shuts, who shuts and no man opens: come, and bring forth the captive from his prison, he who sits in darkness and in the shadow of death.