The following excerpts are taken from book VI, chapter 13, 17-27, of William Durandus’ great liturgical commentary, the Rationale Divinorum Officiorum, his explanation of the three Masses of Christmas. As is his wont, our friend is more than a little prolix and repetitive in this section, and so I have paraphrased him in several places. The traditional story with which he begins, that the feast of Christmas was instituted by Pope Telesphorus, who reigned ca. 126-137, is not historically correct; the feast was instituted at Rome, but about two centuries later. The division of sacred history into four eras, before the Law, under the Law, under Grace, and in peace, is a commonplace in the writings of St Augustine.
Pope Telesphorus established that three Masses are to be sung on this day, to show that the birth of Christ saved the fathers of three eras, namely, those before the law, under the law, and after the law. The first is sung around midnight to show that they who were before the law were not enlightened by any law, and that the bread which is daily sacrificed and eaten on the altar, namely Christ, was born in Bethlehem in the middle of the night, as Luke says, whence also the book of Wisdom (18, 14-15), “while all things were in quiet silence, and the night was in the midst of her course, (Thy almighty word leapt down from heaven)”, which is clearly about the birth of the Lord. … (This text is also the introit of the Sunday within the octave of Christmas.)
The same pope established that in this Mass the angelic hymn, namely, Gloria in excelsis, should be solemnly sung to remind us that the angels sang it on that night when they announced Him to the shepherds, as the Gospel says (Luke 2, 13-14), “And suddenly there was with the Angel a multitude of the heavenly host praising God and saying glory to God in the highest and on earth peace to men of goodwill.”
(This paragraph refers to a custom which is attested in some early Roman lectionaries, and in many medieval uses of the Roman Rite, by which the Mass of the vigil of Christmas, and the three Masses of the feast, had a reading from Isaiah right before the Epistle: 62, 1-3 on the vigil; 9, 2 & 6-7 at the midnight Mass; 61, 1-3 at the dawn Mass; 52, 6-10 at the day Mass. This custom is not evidence of the regular presence of Old Testament reading that later dropped out.)
Immediately before the epistle is read a prophecy… for those things which are said in the Gospel would not be believed unless they had been foretold in the Old Testament. The two lessons are read without interval, one from a prophecy and the other from the Apostle, because Christ is born for the two peoples who are to be joined in (the breaking down of) a wall. (Eph. 2, 14) The column of the Apostles rests upon the base of the prophets, and through both the birth of Christ is harmoniously preached. … however, some do not read any prophecy, signifying that the old things have passed away, and all things are made new (2 Cor. 5, 17), which is to say, the figure ceases because the truth has come. (cf. S. Thomas Aquinas, ST III, Q. 83. a. 2; this part of the Summa is Thomas’ contribution to the genre of liturgical commentary.)
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| Part of a page of Missal according to the use of Augsburg, Germany, printed in 1510. In the left column are the Gospel and Offertory of the dawn Mass of Christmas; in the right column, the introit, collect, and the beginning of the prophecy of Isaiah from the day Mass. |
The second Mass is said at sunrise, at the beginning of the day, when Christ was adored by the shepherds in the crib, and this was done first of all to show that the holy fathers and prophets who were under the written law had a little knowledge of God bit, but not so great as we have now. Therefore, it begins from the promise which was made to the ancients in the old law, “today a light shall shine in the House of the Lord.” …
But the third Mass, which is celebrated in the brightness of the day, at the third hour, when the day of our redemption has shown upon us with greater festivity, refers to the time of grace in which a great light descended from heaven, “which enlightens every man who comes into this world.” (Jo. 1, 9) … the epistle and the gospel are concerned with the eternal generation, whence it says in the former, “Thou art my son, this day have I begotten thee,” … and in the latter, “in the beginning,” as if to say, “at the beginning of creatures was the word.”
The introit of the dawn Mass of Christmas: Lux fulgébit hodie super nos, quia natus est nobis Dóminus, et vocábitur Admirábilis, Deus, Princeps pacis, Pater futúri saeculi: cujus regni non erit finis. Ps. 92 Dóminus regnávit, decórem indútus est: indútus est Dóminus fortitúdinem, et praecinxit se. Gloria Patri... Lux fulgébit... (A light shall shine upon us this day, for the Lord is born to us: and He shall be called Wonderful, God, Prince of peace, Father of the age to come: of Whose reign there shall be no end. Ps. The Lord hath reigned, He is clothed in beauty; that Lord is clothed in strength, and hath girded Himself. Glory be... A light shall shine...)
The first Mass is concerned with the eternal generation. The second is about the promise made to the ancients, which is why it says, “A light will shine in the house of the Lord,” not “shone” or “shines.” The third is about the truth demonstrated to us, which is why it says, “A child is born to us, and a son is given to us.” The one uses the future tense to indicate the promise, the other uses the past tense to indicate the fulfillment of that promise. And because the eternal generation was hidden from us, as Isaiah says (53, 8), “Who shall tell of his generation?”, therefore the Mass about the eternal generation is said in the deep of the night.
The ancient fathers to whom the promise was made were certain of the Lord’s incarnation, but not as much as the fathers of the New Testament to whom the truth was shown, and for this reason the Mass which concerns the promise made to the ancients is sung as the dawn begins to shine, when there is only a little light. … But because the truth is clear in the times of the New Testament, the Mass which is about the demonstration of that truth is sung in the bright light.
Therefore, the first Mass pertains to the eternal generation, that which comes from the Father without a mother; the second to the generation in time, that which is from the Mother without a father; in the third, both are joined together, the eternal generation and the temporal.
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| The Adoration of the Christ Child, with God the Father, 1535-36, by the Italian painter Battista Dossi (ante 1500 - 1548.) |
Nevertheless, it should be noted that in the Mass which is about the eternal generation is read the Gospel about Christ’s humanity, namely, “A decree went forth from Caesar Augustus” (Luke 2, 1-14), but in the other, which is about the truth shown to us, is read the gospel about His divinity, namely, “In the beginning was the word” (John 1, 1-14), to indicate that from the time when the humanity was united to the divinity, the divinity itself was not without the humanity, nor will it ever be. …
The text of the third Mass sounds forth the wonderful deeds of the Word of God, which was “in the beginning” and began to be flesh, as is read in the Gospel. This Word is the Child who according to the prophet has been born to us, as we sing in the introit, and this is the new song of which the prophet speaks in the verse, “Sing to the Lord a new song.” This is also that saving word of which the gradual says, “All the ends of the earth have seen the salvation of our God…” This is the great light which came down into the womb of the virgin, “which enlightens every man who comes into this world…”, finally, He is also that rich and mighty king to whom the offertory says, “thine are the heavens and thine is the earth.”
Offertorium, Ps. 88 Tui sunt caeli, et tua est terra: orbem terrárum et plenitúdinem ejus tu fundasti: justitia et judicium praeparatio sedis tuae. (Thine are the heavens, and Thine is the earth; the world and its fullness Thou hast founded; justice and judgment are the foundation of Thy throne.)
