It identifies our condition before the blood is received in salvation. We were lost, lost forever and hopelessly on our way to eternal condemnation. Sin is a horrible thing and the consequences cannot be escaped unless someone redeems us. In whom we have redemption through his blood, the forgiveness of sins, according to the riches of his grace. There is probably no term in Scripture more breathtaking than this statement.
Sin is dark, destructive, and demonic.
It eats like a cancer and has no pity on its victim. A person in sin will show the continuing effect of the vileness of this dark force in complete discord with all of God's creation. The blood will actually make a soul white in pure form. And I said unto him, Sir, thou knowest. And he said to me, These are they which came out of great tribulation, and have washed their robes, and made them white in the blood of the Lamb.