The Introit for Sunday in the Octave of Christmas: Dum Medium

This Sunday's Introit for the Extraordinary Form is Dum Medium: "While a profound silence."  Here's an mp3 of the chant from  ReneGoupil, and below is the chant score from that site, with their English translation below that.  (The Ordinary Form seems to celebrate "Holy Family Sunday" - but I'm not quite sure about that one; the Brazilian Benedictines say it's on December 30, but I'm not clear whether that's a permanent feast day or whether they're referring to this Sunday only.  In any case, Anglicans don't celebrate that feast, so I'm going with the EF this time.)

While a profound silence enveloped all things, and night was in the midst of her course, your all-powerful Word, O Lord, leaped down from your royal throne.   The Lord reigns, he is enrobed with majesty; the Lord is clothed with strength, he has girded himself.

The first part of the introit comes from a beautiful and obscure text I'd never seen until a couple of years ago:  Wisdom 18:14-15.

14 For when peaceful stillness encompassed everything / and the night in its swift course was half spent,

15 Your all-powerful word from heaven’s royal throne / leapt into the doomed land,

Wisdom 18 recounts, once again, the salvation history of the people of Israel - and this section refers to the last of the 10 plagues when the Israelites were captives in Egypt.  Of course, this is a parallel to what's happening in the New Testament and in the Great Church Year- with a twist.   In Exodus, the people are freed from slavery when Pharoah, after the deaths of the Egyptian first-born, finally releases the Israelites from their bondage; here, the Holy Family is escaping into Egypt because Herod has ordered the death of all boys under the age of 2 years in Bethlehem.   (The Feast of the Holy Innocents was this past Wednesday.)

Psalm 92/93 provides the "He has girded himself with strength" portion of the Introit.

1 The LORD is King;
he has put on splendid apparel; *
the LORD has put on his apparel
and girded himself with strength.
2 He has made the whole world so sure *
that it cannot be moved;
3 Ever since the world began, your throne has been established; *
you are from everlasting.
4 The waters have lifted up, O LORD,
the waters have lifted up their voice; *
the waters have lifted up their pounding waves.
5 Mightier than the sound of many waters,
mightier than the breakers of the sea, *
mightier is the LORD who dwells on high.
6 Your testimonies are very sure, *
and holiness adorns your house, O LORD,
for ever and for evermore.

I'm not sure what sort of thing this is; it starts out using this text and then goes someplace else.  It's beautiful, though, so here it is - sung by "Ensemble Gilles Binchois, Dominique Vellard, dir. Le Chant des Cathédrales - Ecole de Notre Dame de Paris" :




And, wow!  The various lectionaries for this Sunday are really all over the place.  The RCL has three different readings for Years A, B, and C; the first is indeed the flight into Egypt - but the others are the Purification (i.e., Simeon and Anna in the temple), and Jesus' adventures as a boy in the temple.   The 1928 and 1662 BCPs both had Matthew's story of Jesus' birth; the 1979 BCP has the Prologue of John on this Sunday for every year (I like this last choice, myself),

Just for the sake of coherence with the chant proper, here's RCL-A: the flight into Egypt from Matthew 2:13-23:

2:13 Now after they had left, an angel of the Lord appeared to Joseph in a dream and said, "Get up, take the child and his mother, and flee to Egypt, and remain there until I tell you; for Herod is about to search for the child, to destroy him."

2:14 Then Joseph got up, took the child and his mother by night, and went to Egypt,

2:15 and remained there until the death of Herod. This was to fulfill what had been spoken by the Lord through the prophet, "Out of Egypt I have called my son."

2:16 When Herod saw that he had been tricked by the wise men, he was infuriated, and he sent and killed all the children in and around Bethlehem who were two years old or under, according to the time that he had learned from the wise men.

2:17 Then was fulfilled what had been spoken through the prophet Jeremiah:

2:18 "A voice was heard in Ramah, wailing and loud lamentation, Rachel weeping for her children; she refused to be consoled, because they are no more."

2:19 When Herod died, an angel of the Lord suddenly appeared in a dream to Joseph in Egypt and said,

2:20 "Get up, take the child and his mother, and go to the land of Israel, for those who were seeking the child's life are dead."

2:21 Then Joseph got up, took the child and his mother, and went to the land of Israel.

2:22 But when he heard that Archelaus was ruling over Judea in place of his father Herod, he was afraid to go there. And after being warned in a dream, he went away to the district of Galilee.

2:23 There he made his home in a town called Nazareth, so that what had been spoken through the prophets might be fulfilled, "He will be called a Nazorean."

Here's the Collect  (which sure seems to parallel the Prologue of John!):

Almighty God, you have poured upon us the new light of your incarnate Word: Grant that this light, enkindled in our hearts, may shine forth in our lives; through Jesus Christ our Lord, who lives and reigns with you, in the unity of the Holy Spirit, one God, now and for ever. Amen.

I don't have Hatchett's commentary on this, but here's a bit about the collect from Trinity Episcopal in Concord, MA:

The familiar theme in this Collect of “the new light that shines forth” was initially part of the Gregorian Sacramentary and later included in the Sarum Rite. It was eventually included in our 1928 BCP revision for the Second Sunday after Christmas. The late Massey Shepherd, who wrote the Commentary on the 1928 Prayer Book, felt that the Collect was more associated with the translation by the Rev. Arwell M.Y. Bayley that was included in his book, “A Century of Collects,” published in 1913. The Petition Clause in the original Latin could be translated as, “Grant that the light which through faith shines in the heart, may shine forth in our works,” thus picking up the relationship between faith and works. The juxtaposition of darkness and light has been with us from the beginning of creation as described in Genesis. The “new light” of Christ is particularly found in this Sunday’s reading from The Gospel of John, as well as our hymns, and our sermons, encouraging and inspiring us to go forth into the world to love and serve God.

Here's the flight into Egypt four ways.  In order:   Giotto (late C13/early C14); Joachim Beuckelaer (2nd half of C16); George Hitchcock (1892); and Henry Ossawa Tanner (1923).