Luke 2:1-20: "1 In those days a decree went out from Caesar Augustus that all the world should be registered. 2 This was the first registration when Quirinius was governor of Syria. 3 And all went to be registered, each to his own town. 4 And Joseph also went up from Galilee, from the town of Nazareth, to Judea, to the city of David, which is called Bethlehem, because he was of the house and lineage of David, 5 to be registered with Mary, his betrothed, who was with child. 6 And while they were there, the time came for her to give birth. 7 And she gave birth to her firstborn son and wrapped him in swaddling cloths and laid him in a manger, because there was no place for them in the inn.
"8 And in the same region there were shepherds out in the field, keeping watch over their flock by night. 9 And an angel of the Lord appeared to them, and the glory of the Lord shone around them, and they were filled with fear. 10 And the angel said to them, 'Fear not, for behold, I bring you good news of great joy that will be for all the people. 11 For unto you is born this day in the city of David a Savior, who is Christ the Lord. 12 And this will be a sign for you: you will find a baby wrapped in swaddling cloths and lying in a manger.' 13 And suddenly there was with the angels a multitude of the heavenly host praising God and saying, 14 'Glory to God in the highest, and on earth peace among those with whom he is pleased!'
"15 When the angels went away from them into heaven, the shepherds said to one another, 'Let us go over to Bethlehem and see this thing that has happened, which the Lord has made known to us.' 16 And they went with haste and found Mary and Joseph, and the baby lying in a manger. 17 And when they saw it, they made known the saying that had been told them concerning this child. 18 And all who heard it wondered at what the shepherds told them. 19 But Mary treasured up all these things, pondering them in her heart. 20 And the shepherds returned, glorifying and praising God for all they had heard and seen, as it had been told them."
Philippians 2:5-11: "5 Have this mind among yourselves, which is yours in Christ Jesus, 6 who, though he was in the form of God, did not count equality with God a thing to be grasped, 7 but made himself nothing, taking the form of a servant, being born in the likeness of men. 8 And being found in human form, he humbled himself by becoming obedient to the point of death, even death on a cross. 9 Therefore God has highly exalted him and bestowed on him the name that is above every name, 10 so that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, 11 and every tongue confess that Jesus Christ is Lord, to the glory of God the Father."
1 John 3:5: "You know that he appeared to take away sins, and in him there is no sin."
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The text is public domain:
Gentle Mary laid her child
Lowly in a manger;
There He lay, the Undefiled,
To the world a stranger.
Such a babe in such a place,
Can He be the Savior?
Ask the saved of all the race
Who have found His favor.
Angels sang about His birth,
Wise Men sought and found Him;
Heaven's star shone brightly forth
Glory all around Him.
Shepherds saw the wondrous sight,
Heard the angels singing;
All the plains were lit that night,
All the hills were ringing.
Gentle Mary laid her child
Lowly in a manger;
He is still the Undefiled
But no more a stranger.
Son of God of humble birth,
Beautiful the story;
Praise His name in all the earth;
Hail the King of glory!
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As is apparently the case for most Christmas hymns, the Luke 2 text is the primary source, with all three verses referring to it.
The Philippians text appears most obviously in "Son of God of humble birth." It could be hinted at with the lines "Praise His name in all the earth; / Hail the King of glory!" although this could also be from the end of the Luke 2 text.
The parts of the hymn that come from the 1 John text don't retain its specific phrasing. "You know that he appeared to take away sins" seems to be obliquely referred to with the lines "Can He be the Savior? / Ask the saved of all the race / Who have found His favor." "In him there is no sin" is represented with the two lines that call Jesus "the Undefiled."
The Philippians text appears most obviously in "Son of God of humble birth." It could be hinted at with the lines "Praise His name in all the earth; / Hail the King of glory!" although this could also be from the end of the Luke 2 text.
The parts of the hymn that come from the 1 John text don't retain its specific phrasing. "You know that he appeared to take away sins" seems to be obliquely referred to with the lines "Can He be the Savior? / Ask the saved of all the race / Who have found His favor." "In him there is no sin" is represented with the two lines that call Jesus "the Undefiled."
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Near the beginning of the second verse, the lines "Wise Men sought and found Him; / Heaven's star shone brightly forth / Glory all around Him" come from (the un-cited) Matthew 2, the account of the wise men following the star to Jesus.
Again, as seems common for Christmas hymns, the angels are portrayed as singing: "Angels sang about His birth," and the shepherds "Heard the angels singing." In the Luke text, however, a single angel announces the birth ("the angel said to them, 'Fear not...'"), and "a multitude of the heavenly host [appear] praising God and saying, 'Glory to God in the highest....'"