Luke 3:4-5: "As it is written in the book of the words of Isaiah the prophet, 'The voice of one crying in the wilderness: "Prepare the way of the Lord, make his paths straight. Every valley shall be filled, and every mountain and hill shall be made low, and the crooked shall become straight, and the rough places shall become level ways."'"
1 Peter 5:5b-6: "Clothe yourselves, all of you, with humility toward one another, for 'God opposes the proud but gives grace to the humble.'
"Humble yourselves, therefore, under the mighty hand of God so that at the proper time he may exalt you."
Psalm 51:10-12: "Create in me a clean heart, O God, and renew a right spirit within me. Cast me not away from your presence, and take not your Holy Spirit from me. Restore to me the joy of your salvation, and uphold me with a willing spirit."
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The text is public domain:
Arise, O Christian people!
Prepare yourselves today;
Prepare to greet the Savior,
Who takes your sins away.
To us by grace alone
The truth and light were given;
The promised Lord for heaven
To all the world is shown.
Prepare the way before Him;
Prepare for Him the best.
Cast out what would offend Him,
This great, this heav'nly guest.
Make straight, make plain the way:
The lowly valleys raising,
The heights of pride abasing,
His path all even lay.
The humble heart and lowly
God raises up on high;
Beneath His feet in terror
The haughty soul shall lie.
The heart sincere and right,
That heeds God's invitation
And makes true preparation -
It is the Lord's delight.
Prepare my heart, Lord Jesus;
Turn not from me aside,
And help me to receive You
This blessed Adventtide.
From stall and manger low
Come now to dwell within me;
I'll sing Your praises gladly
And forth Your glory show.
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The Biblical references in this hymn are pretty clear cut. The second verse comes from the Luke 3 text (which itself quotes Isaiah 40), and although it precedes the second verse, the first verse extends the idea of "Prepare the way of the Lord." The 1 Peter text forms the basis of the third verse, and Psalm 51 is the basis of the last verse.
