Isaiah 6:5

2 Above him stood the seraphim: each one had six wings; with twain he covered his face, and with twain he covered his feet, and with twain he did fly.

3 And one cried unto another, and said, Holy, holy, holy, is Jehovah of hosts: the whole earth is full of his glory.

4 And the foundations of the thresholds shook at the voice of him that cried, and the house was filled with smoke.

5 Then said I, Woe is me! for I am undone; because I am a man of unclean lips, and I dwell in the midst of a people of unclean lips: for mine eyes have seen the King, Jehovah of hosts.

6 Then flew one of the seraphim unto me, having a live coal in his hand, which he had taken with the tongs from off the altar:

7 and he touched my mouth with it, and said, Lo, this hath touched thy lips; and thine iniquity is taken away, and thy sin forgiven.

8 And I heard the voice of the Lord, saying, Whom shall I send, and who will go for us? Then I said, Here am I; send me.