11 And We further desire that with the same spiritual ardor for this cause prayers be repeatedly offered during the novena of supplication customarily held in preparation for the solemn feast of the Birth of Jesus Christ, to beseech the Divine Infant that the peace proclaimed above His sacred crib by angelic choirs to men of good will ( Luke 2, 14) may shine forth throughout the world and become firmly established everywhere.
Source: Mirabile Illud (Vatican.va)