Pope St. Leo the Great Sermon 25 The Nativity of the Lord CHAPTER 1 My beloved people, although the birth of our Lord Jesus Christ, by which he clothed himself with the flesh of our nature, is ineffable, I make bold to speak, not trusting in my skill, but relying on his inspiration, so that in this way, on the day which was chosen for the mystery [sacrament] of the restoration of man, we may offer something that can edify those who hear it
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Christmas Sermon 25 of Leo the Great