The ancient tradition of singing the “O Antiphons” during the Liturgy of the Hours and in place of the Alleluia verse at Mass begins on Dec. 17 and continues through Dec. 23. Each O Antiphon combines a laudatory invocation of the expected Messiah with a petition for His coming as Savior on Christmas Day.
https://marian.org/articles/contemplating-christmas-end-semester"Ennoble the Church, make it beautiful," Fr. Kaz, MIC, tells Br. Josh, MIC. "This means teach, guide,and share all the ‘pieces’ of your life for this precious friend of yours, Mary."