O Sapinetia quae ex ore Altissimi prodiisti, attingens a fine usque ad finem, fortiter sauviterque disponens omnia: veni ad docendum nos viam prudentiae.
O Wisdom, you came forth from the mouth of the Most High, and reached from end to end, and disposed of all things sweetly and mightly: come and teach us the way of prudence!
You can hear the Great O Antiphons here...
I absolutely love this part of Advent as our liturgical sensibility starts to be centrally focussed on the birth of the Savior, Emmanuel. At Vespers the antiphon for the Magnificat hymn in the Divine Office shows us the solemnity of the next days. The first antiphon is noted above in Latin and in English. Each of the antiphons appeals to the Old Testament types given to tell of the coming of the Messiah. The OT typology indicates the new dispensation of grace. Today, we ask for a new sense of prudence rooted in Christ.
And NOW we are able to sing the famous Advent hymn O Come, O Come Emmanuel. It is only tonight that singing the hymn makes any real sense as opposed to singing it when Advent begins, a common mistake.
I was reading a bit on Advent in Father Pius Parsch's The Church's Year of Grace:
"Come, teach us the way of prudence! What an all-embracing petition! Make us perfect Christians, Christians who are wholly penetrated --mind, will, and emotions-- with the leaven of Christianity. Make us true Christian personalities who combine strength with gentleness. Make us strong in battle against hell, the world and self; make us glow with the love of God and neighbor! Enable us to show virile courage, and heroism unto martyrdom. Enable us to show the virgin gentleness and sweetness of a bride. In this sense we pray, "Thy kingdom come!" All this is part of our yearning plea, Come! teach us the way of prudence.