Here’s some church nerd trivia for you! “O Come, O Come, Emmanuel” is not a Christmas song, but an Advent hymn. Each stanza is a prayer inspired by each of the seven days leading up to December 25th. Medieval Christians called these the “O Antiphons,” because each of the prayers begins by addressing the Son of God by an Old Testament name. This fifth stanza addresses Christ, “O Morning Star/Oriens!”