In Isaiah’s vision, the seraphim repeatedly declare God as “holy” and say “the whole earth is full of his glory” (Isaiah 6:3). The statement is part of the throne-room scene where God’s presence causes shaking and smoke in the temple (Isaiah 6:4).
Isaiah dates his experience to the year King Uzziah died and reports seeing the Lord enthroned in the temple, towering in majesty as the robe’s trailing hem fills the space. Heavenly attendants (seraphim) stand above, using their six wings for covering and for flight. Within Isaiah, this scene functions as a throne-room vision that introduces the prophet’s commissioning narrative (continuing in Isaiah 6:5–8).
Isaiah locates this scene in a moment of national transition: “the year King Uzziah died.” In that setting he reports a throne-room vision centered in the temple. The Lord is presented as the true king—“high and lifted up”—and the imagery of the robe’s trailing hem filling the temple communicates overwhelming majesty and presence (textual claim).
A common mistake is to turn the wording into a slogan. The better reading keeps the phrase tied to the passage, the speaker, and the problem the book is addressing.
Start with Isaiah 6:3, then read the surrounding section so the answer stays connected to the passage's flow.
3One cried to another, and said, Holy, holy, holy, is Yahweh of Hosts: the whole earth is full of his glory.