Isaiah 6:2-4

Seraphim stood above Him, each having six wings: with two he covered his face, and with two he covered his feet, and with two he flew. And one called out to another and said, “Holy, Holy, Holy, is the LORD of hosts, The whole earth is full of His glory.” And the foundations of the thresholds trembled at the voice of him who called out, while the temple was filling with smoke.