Since the time of Boethius in the fifth century, Christian people have been encouraged to think from 16-23 December each year of the coming Messiah using his messianic titles. Before Magnificat was said or sung at Vespers during these days one of those titles would be used as an antiphon.
The Benedictine monks went on to arrange these seven antiphons with a definite purpose. If we start with the last title which we think of on this day and then take the first letter of each of the following ones in order – Emmanuel, Rex, Oriens, Clavis, Radix, Adonai, Sapientia – the Latin words ero cras are formed, meaning, Tomorrow, I will come.
Therefore, Jesus of Nazareth, whose coming, the celebration of whose blooming bright in the world we have been trying to prepare for throughout this Advent and whom we may address in these seven holy Messianic titles, now speaks to us, Tomorrow, I will come.
So the “O Antiphons” not only bring intensity to our Advent preparation, but bring it to a joyful conclusion.
O Emmanuel, king and lawgiver, desire of the nations, Saviour of all people, come and set us free, Lord our God.