Isaiah 6:2-3: "2 Above him [the Lord] stood the seraphim. Each had six wings: with two he covered his face, and with two he covered his feet, and with two he flew. 3 And one called to another and said: 'Holy, holy, holy is the LORD of hosts; the whole earth is full of his glory!'"
2 Corinthians 3:14: "But their minds [the Israelites'] were hardened. For to this day, when they read the old covenant, that same veil remains unlifted, because only through Christ is it taken away."
Psalm 145:10: "All your works shall give thanks to you, O LORD, and all your saints shall bless you!"
Psalm 145:21: "My mouth will speak the praise of the LORD, and let all flesh bless his holy name forever and ever."
Psalm 86:12: "I give thanks to you, O Lord my God, with my whole heart, and I will glorify your name forever."
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The text is public domain:
Father most holy, merciful, and tender;
Jesus, our Savior, with the Father reigning;
Spirit of comfort, advocate, defender,
Light never waning;
Trinity blessed, unity unshaken,
Goodness unbounded, very God of heaven,
Light of the angels, joy of those forsaken,
Hope of all living,
Maker of all things, all Thy creatures praise Thee;
All for Thy worship were and are created;
Now, as we also worship Thee devoutly,
Hear Thou our voices.
Lord God Almighty, unto Thee be glory,
One in three persons, over all exalted!
Glory we offer, praise Thee and adore Thee,
Now and forever.
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The "holy, holy, holy" from Isaiah 6:3 seems to be condensed into "most holy" in the first line.
The two verses from Psalm 145 seem to be combined into the hymn's third verse. Psalm 145:10 shows up a bit more clearly because of the resemblance between its "All your works" and the hymn's "Maker of all things," but the two Psalm verses and the hymn verse all mention the entirety of God's creation praising Him.
The "glorif[ing]... forever" from Psalm 86:12 appears in the last verse.
I don't see how 2 Corinthians 3:14 relates to the hymn, and because the tone is so different, I'm suspicious that this citation was meant to be a different verse.
