12 Venerable brethren, may He who is the beginning and end of every good work inspire your and Our endeavors. And, indeed, the very thought of these days, in which the anniversary of our Lord's birth is solemnly observed, moves us to hope for speedy help. For the new life which Christ at His birth brought to a world already aging and steeped in the very depths of wickedness He bids us also to hope for, and the peace which He then announced by the angels to men He has promised to us also. For the Lord's "hand is not shortened that he cannot save, neither is his ear heavy that he cannot hear."(19) In these most auspicious days, then, venerable brethren, wishing all joy and happiness to you and to the faithful of your churches, We earnestly pray the Giver of all good that again "there may appear unto men the goodness and kindness of God our Saviour,"(20) who brought us out of the power of our most deadly enemy into the most noble dignity of the sons of God. And that We may the sooner and more fully gain our wish, do you, venerable brethren, join with Us in lifting up your fervent prayers to God and beg the intercession of the Blessed and Immaculate Virgin Mary, and of Joseph her spouse, and of the blessed Apostles Peter and Paul, in whose prayers We have the greatest confidence. And in the meanwhile We impart to you, with the inmost affection of the heart, and to your clergy and faithful people, the apostolic benediction as an augury of the divine gifts. Given at St. Peter's, in Rome, on the twenty-eighth day of December, 1878, in the first year of Our pontificate.
Source: Quod Apostolici Muneris (Vatican.va)