Psalm 150: "1 Praise the LORD! Praise God in his sanctuary; praise him in his mighty heavens! 2 Praise him for his mighty deeds; praise him according to his excellent greatness!
"3 Praise him with trumpet sound; praise him with lute and harp! 4 Praise him with tambourine and dance; praise him with strings and pipe! 5 Praise him with sounding cymbals; praise him with loud clashing cymbals! 6 Let everything that has breath praise the LORD! Praise the LORD!"
Isaiah 6:1-4: "1 In the year that King Uzziah died I saw the Lord sitting upon a throne, high and lifted up; and the train of his robe filled the temple. 2 Above him 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!' 4 And the foundations of the thresholds shook at the voice of him who called, and the house was filled with smoke."
Revelation 4:8: "And the four living creatures, each of them with six wings, are full of eyes all around and within, and day and night they never cease to say, 'Holy, holy, holy, is the Lord God Almighty, who was and is and is to come!'"
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The text is public domain:
Praise God, from whom all blessings flow;Praise Him, all creatures here below;Praise Him above, ye heav'nly host:Praise Father, Son, and Holy Ghost.Amen.
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Psalm 150 is the main source for the hymn; both texts repeated exhort one to praise the Lord. The other two citations are summarized in the line "Praise Him above, ye heav'nly host."
