At Midnight Mass in Saint Peter's Pope Benedict concluded his homily with these words:

Saint Luke does not say that the angels sang. He states quite soberly: the heavenly host praised God and said: Glory to God in the highest (Lk 2:13f.). But men have always known that the speech of angels is different from human speech, and that above all on this night of joyful proclamation it was in song that they extolled Gods heavenly glory. So this angelic song has been recognized from the earliest days as music proceeding from God, indeed, as an invitation to join in the singing with hearts filled with joy at the fact that we are loved by God. Cantare amantis est, says Saint Augustine: singing belongs to one who loves. Thus, down the centuries, the angels song has again and again become a song of love and joy, a song of those who love. At this hour, full of thankfulness, we join in the singing of all the centuries, singing that unites heaven and earth, angels and men. Yes, indeed, we praise you for your glory. We praise you for your love. Grant that we may join with you in love more and more and thus become people of peace. Amen.