Isaiah 6:5-7

I said, “Oh, no! I will be destroyed. I am not pure, and I live among people who are not pure, but I have seen the King, the LORD All-Powerful.” One of the heavenly creatures used a pair of tongs to take a hot coal from the altar. Then he flew to me with the hot coal in his hand. The creature touched my mouth with the hot coal and said, “Look, your guilt is taken away, because this hot coal has touched your lips. Your sin is taken away.”