Revelation 5:8

And, when he had taken the book, the four Creatures and the twenty-four Councillors prostrated themselves before the Lamb, each of them holding a harp and golden bowls full of incense. (These are the prayers of Christ's People.)

Revelation 14:2-3

And I heard a sound from Heaven, 'like the sound of many waters,' and like the sound of a loud peal of thunder; the sound that I heard was like the music of harpers playing on their harps.

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