Luke 4:18-19: "'The Spirit of the Lord is upon me, because he has anointed me to proclaim good news to the poor. He has sent me to proclaim liberty to the captives and recovering of sight to the blind, to set at liberty those who are oppressed, to proclaim the year of the Lord's favor.'"
Isaiah 40:3: "A voice cries: 'In the wilderness prepare the way of the LORD; make straight in the desert a highway for our God.'"
Isaiah 61:1-2: "The Spirit of the Lord GOD is upon me, because the LORD has anointed me to bring good news to the poor; he has sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to those who are bound; to proclaim the year of the LORD's favor, and the day of vengeance of our God; to comfort all who mourn."
Matthew 21:9: "And the crowds that went before him and that followed him were shouting, 'Hosanna to the Son of David! Blessed is he who comes in the name of the Lord! Hosanna in the highest!'"
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The text is public domain:
Hark the glad sound! The Savior comes,
The Savior promised long;
Let ev'ry heart prepare a throne
And ev'ry voice a song.
He comes the pris'ners to release,
In Satan's bondage held.
The gates of brass before Him burst,
The iron fetters yield.
He comes the broken heart to bind,
The bleeding soul to cure,
And with the treasures of His grace
To enrich the humble poor.
Our glad hosannas, Prince of Peace,
Thy welcome shall proclaim,
And heav'n's eternal arches ring
With Thy beloved name.
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The first verse seems to be an extension of the sentiments in the Matthew 21 and Isaiah 40 texts cited. "The glad sound" is that of the people's "shouting, 'Hosanna to the Son of David!'" in Matthew, and "Let ev'ry heart prepare a throne / And ev'ry voice a song" has the same sort of structure as Isaiah's "prepare the way of the LORD; make straight in the desert a highway." Instead of a way and a highway, there's the call to prepare a throne and a song.
The second and third verses come from the Isaiah 61 text, which is quoted by Christ in Luke 4. The lines "He comes the broken heart to bind, / The bleeding soul to cure" also seem to come from Psalm 147:3 (which isn't cited in the hymnal): "He heals the brokenhearted and binds up their wounds."
The fourth verse - with its specific mention of hosannas - is also from the Matthew text. The name "Prince of Peace" comes from Isaiah 9:6 (which also isn't cited): "For to us a child is born, to us a son is given; and the government shall be upon his shoulder, and his name shall be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace."
