Isaiah 6:4-7, "The house filled with smoke. And 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.”
Then one of the seraphs flew to me, holding a live coal that had been taken from the altar with a pair of tongs. The seraph touched my mouth with it and said: “Now that this has touched your lips, your guilt is taken away and your sin is blotted out.""
People use this passage from Isaiah to say that we should be broken over our sin or hate our sin or feel shame for our sin. But notice these things that speak to the contrary.
The house filled with the smoke of the coals before Isaiah said anything. God had the coal ready for Isaiah before he even got there. God had the removal of sin & guilt ready for Isaiah. It wasn't dependent upon what Isaiah said or felt about Himself.
God didn't call Isaiah an unclean man or tell Him to feel ruined. I repeat, despite the fact that Isaiah had sin God did not call him out for it or even address what Isaiah said. God didn't condemn Isaiah instead He cleansed him. He immediately took His sin & guilt away. This is the same way Jesus treated Peter when Peter said, "Depart from me because I am a sinful man, Lord." Jesus ignored Peter's sin & simply said to him, "Do not fear. Come with me." The father in the parable of the prodigal son did the same thing as well. The son said, "Father, I have sinned against heaven and in your sight; I am no longer worthy to be called your son." But the father ignored the sin and feelings of shame and immediately said, "Quick let's celebrate because my son is now with me!" God did not command or endorse what Isaiah felt about himself thus there is no reason at all for us to say we should feel like Isaiah did here. The opposite is in fact true. God doesn't need you to feel bad about your sin He just wants to heal you & move on.
Once Isaiah's sin was blotted out he didn't continue to feel guilty or speak in shame. Christ has already forever taken away our guilt & our sin thus we have no reason to ever feel woeful, ruined, sinful, or unclean because of things we have done. Our spirits have been united with the King.
An unsaved man need only know that he is sick & ask God for the cure, he doesn't have to beat himself up about how sick he is for God to cure him. A saved man has already been cured. Saved actually means cured/made whole. There is no sense in wallowing in a sickness that is already gone. God refused to be conscious of the guilt of Isiah's & Peter's sins even while they tried to confess them. He loves them & sought only to save them, not to shame them. Likewise Jesus pictured the Father in the prodigal son story as treating everyone without ever using a moment of shame or guilt. Let that sink in..
Sin makes unsaved men feel guilt & shame, that is a fact God has to live with but He'll do all He can to not give aid to those feelings for even a moment. Jesus felt our shame on the cross & He despised it (1 of only 2 things the NT says Jesus hates). He despised the way shame made us feel far from Him & unloved by Him. His heart was broken & crushed feeling empathy, pity, & compassion for our shame.
God already condemned sin on the cross. God doesn't demand you join in on His sin hating party, He's not having one. He instead invites you to celebrate in His victory party. The victory that freed us from having to be conscious of sin & freed us from having to feel guilt & shame.