Galatians 4:4-5: "4 But when the fullness of time had come, God sent forth his Son, born of woman, born under the law, 5 to redeem those who were under the law, so that we might receive adoption as sons."
2 Timothy 1:10: "and which [God's "purpose and grace"] now has been manifested through the appearing of our Savior Christ Jesus, who abolished death and brought life and immortality to light through the gospel."
1 John 4:9: "In this the love of God was made manifest among us, that God sent his only Son into the world, so that we might live through him."
Luke 1:30-35: "30 And the angel said to her, 'Do not be afraid, Mary, for you have found favor with God. 31 And behold, you will conceive in your womb and bear a son, and you shall call his name Jesus. 32 He will be great and will be called the Son of the Most High. And the Lord God will give to him the throne of his father David, 33 and he will reign over the house of Jacob forever, and of his kingdom there will be no end.'
"34 And Mary said to the angel, 'How will this be, since I am a virgin?'
"35 And the angel answered her, 'The Holy Spirit will come upon you, and the power of the Most High will overshadow you; therefore the child to be born will be called holy - the Son of God.'"
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The text is public domain:
The only Son from heaven,
Foretold by ancient seers,
By God the Father given,
In human form appears.
No sphere His light confining,
No star so brightly shining
As He, our Morning Star.
O time of God appointed,
O bright and holy morn!
He comes, the king anointed,
The Christ, the virgin-born,
Grim death to vanquish for us,
To open heav'n before us
And bring us life again.
O Lord, our hearts awaken
To know and love You more,
In faith to stand unshaken,
In spirit to adore,
That we, through this world moving,
Each glimpse of heaven proving,
May reap its fullness there.
O Father, here before You
With God the Holy Ghost
And Jesus, we adore You,
O pride of angel host:
Before You mortals lowly
Cry, "Holy, holy, holy,
O blessed Trinity!"
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The first verse comes from Galatians 4:4-5, although the name "Morning Star" comes from Revelation 22:16. The second verse seems to take something from the Galatians text too ("O time of God appointed"), but it also uses Luke 1:30-35 (the description of "virgin-born"), 2 Timothy 1:10 ("Grim death to vanquish for us"), and 1 John 4:9 ("To open heav'n before us / And bring us life again").
There don't seem to be any Biblical references in the second half of the hymn, although "Before You mortals lowly / Cry 'Holy, holy, holy...'" bears some resemblance to Isaiah 6:3 ("'Holy, holy, holy is the LORD of hosts...'").
