Book of Isaiah 6:1-8.
In the year King Uzziah died, I saw the Lord seated on a high and lofty throne, with the train of his garment filling the temple.
Seraphim were stationed above; each of them had six wings: with two they veiled their faces, with two they veiled their feet, and with two they hovered aloft.
“Holy, holy, holy is the LORD of hosts!” they cried one to the other. “All the earth is filled with his glory!”
At the sound of that cry, the frame of the door shook and the house was filled with smoke.
Then I said, “Woe is me, I am doomed! For I am a man of unclean lips, living among a people of unclean lips; yet my eyes have seen the King, the LORD of hosts!”
Then one of the seraphim flew to me, holding an ember which he had taken with tongs from the altar.
He touched my mouth with it. “See,” he said, “now that this has touched your lips, your wickedness is removed, your sin purged.”
Then I heard the voice of the Lord saying, “Whom shall I send? Who will go for us?” “Here I am,” I said; “send me!”