A much-loved Christian hymn has this title, and the Catholic mass uses it. In the Bible it is found in Isaiah’s vision in the temple, where he sees seraphs (angels) calling to one another: “Holy, holy, holy is the LORD of hosts; the whole earth is full of His glory!” (Isa. 6:3). A similar vision is found in Revelation 4:8: “Holy, holy, holy, Lord God Almighty, who was and is and is to come!”
