Today the Church enters into the most holy of days prior to the Solemnity of Christmas. These holy days are marked by the “O Antiphons” prayed at Mass and in the prayer of the Church – the liturgy of the hours. I like the way catholicculture.com put it: “December 17 marks the beginning of the “O” Antiphons, the seven jewels of our liturgy, dating back to the fourth century, one for each day until Christmas Eve. These antiphons address Christ with seven magnificent Messianic titles, based on the Old Testament prophecies and types of Christ. The Church recalls the variety of the ills of man before the coming of the Redeemer.”
O Sapientia (December 17) “O Wisdom”, O holy Word of God, you govern all creation with your strong yet tender care. Come and show your people the way to salvation.” Isaiah had prophesied, “The spirit of the Lord shall rest upon him: a spirit of wisdom and of understanding, a spirit of counsel and of strength, a spirit of knowledge and fear of the Lord, and his delight shall be the fear of the Lord.” (11:2-3), and “Wonderful is His counsel and great is His wisdom.” (28:29).
~ Fr. William Sanders
I want to reiterate that the significance of the O Antiphons is twofold:
1) If refers to one of the 7 messianic titles given to Christ.
2) They are linked with 7 prophecies regarding the Messiah from the Prophet Isaiah.