Isaiah 6:5 NASB
“Then I said, “Woe is me, for I am ruined! Because I am a man of unclean lips, And I live among a people of unclean lips; For my eyes have seen the King, the Lord of hosts.””
Why does Isaiah focus on the impurity of lips here as opposed to, say, impurity of the heart which is mentioned often in other parts of scripture? Assuming this happens before he offers himself as the mouthpiece of God, is it to show that he realizes the uncleanliness of his mouth?
This chapter deals with a vision that Isaiah the prophet sees. We can see how he identifies himself 6 times within the verse:
“Then I said, “Woe is me, for I am ruined! Because I am a man of unclean lips, And I live among a people of unclean lips; For my eyes have seen the King, the Lord of hosts.” [emphasis mine]
Isaiah was chosen as a prophet by Jehovah God himself therefore Isaiah would have to have been a man of faith (see Hebrews 11:1, 32). Jehovah God uses or chooses those that have the right heart condition and faith to minister to his people.
So what did Isaiah mean by "impurity of lips"? We can see that the Bible uses lips to represent speech or language:
When there are many words, wrongdoing is unavoidable, But one who restrains his lips is wise. (Proverbs 10:19 NASB)
2 We all stumble in many ways. If anyone is never at fault in what he says, he is a perfect man, able to control his whole body. . . . 6 The tongue also is a fire, a world of wickedness among the parts of the body. It pollutes the whole person, sets the course of his life on fire, and is itself set on fire by hell. (James 3:2, 6 NASB)
As a human being, Isaiah recognized that he may have been harsh or unkind in his words. Does that mean that his heart was wicked? No, because Jehovah God would not have used him to give the nation of Israel warnings and hope for the future.
