Alma 5:22-23
I think that Alma is explaining the guilt of those who stand before God with fear and trembling. He would know such guilt because he felt it before he came to repentance. How would I feel standing before the Lord, who is spotless, on my stained garments after refusing to let Him wash the stains away. How would I feel with blood to testify of my murders and other filthiness to testify of each of my other sins. I would be ashamed to be in His presence with that blatant evidence that I was defiling His house.