Isaiah 6:2-6

2Seraphim were standing above him; they each had six wings: with two they covered their faces, with two they covered their feet, and with two they flew.

3And one called to another: Holy, holy, holy is the Lord of Armies; his glory fills the whole earth.

4The foundations of the doorways shook at the sound of their voices, and the temple was filled with smoke.

5Then I said: Woe is me for I am ruined because I am a man of unclean lips and live among a people of unclean lips, and because my eyes have seen the King, the Lord of Armies.

6Then one of the seraphim flew to me, and in his hand was a glowing coal that he had taken from the altar with tongs.