Isa 6:2-7

2Seraphs were in attendance above him; each had six wings: with two they covered their faces, and with two they covered their feet, and with two they flew.3And one called to another and said: “Holy, holy, holy is the Lord of hosts; the whole earth is full of his glory.”4The pivots on the thresholds shook at the voices of those who called, and the house filled with smoke.5And I said: “Woe is me! I am lost, for I am a man of unclean lips, and I live among a people of unclean lips; yet my eyes have seen the King, the Lord of hosts!”6Then one of the seraphs flew to me, holding a live coal that had been taken from the altar with a pair of tongs.7The seraph touched my mouth with it and said: “Now that this has touched your lips, your guilt has departed and your sin is blotted out.”