Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
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Revelation 4:8

The four living creatures, each one of them having six wings, are full of eyes around and within. They have no rest day and night, saying, “Holy, holy, holy is the Lord God, the Almighty, who was and who is and who is to come!”

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