Then one of the seraphim flew to me with a burning coal in his hand, which he had taken from the altar with tongs. He touched my mouth with it and said, "Behold, this has touched your lips; and your iniquity is taken away and your sin is forgiven". (please read vv. 5-7)
Brokenness and confession from me lead to forgiveness and restoration from God!
The angel touched Isaiah's lips with a coal from the sacrificial altar. God gave the people of Israel the sacrificial system as a symbol of what Christ would do for them at the cross. Jesus had not yet come and so God gave them the symbol of the substitutionary death of an animal as payment for their sins. But really it was the great sacrifice of Jesus for us that would make a way for our sins to be "taken away" and "forgiven".
After Isaiah's heart cry of brokenness and despair over his own sin, "then" came God's forgiveness.
God's reminding you today that He doesn't want you to downplay your sin and make it seem not so bad. What He responds to in your life is open confession and grief in your heart about your sin against Him. And He's also assuring you that when you see your sin the way He sees it and come to Him with it, He's so ready to restore your relationship with Him to relational closeness.