Isaiah 6:5-7

5I said, “Too bad for me! I am destroyed, for my lips are contaminated by sin, and I live among people whose lips are contaminated by sin. My eyes have seen the king, the Lord who commands armies.”

6But then one of the seraphs flew toward me. In his hand was a hot coal he had taken from the altar with tongs.

7He touched my mouth with it and said, “Look, this coal has touched your lips. Your evil is removed; your sin is forgiven.”