what does Raskolnikov experience in connection with the bloodstained sock?

Raskolnikov obviously experiences a great deal of guilt regarding his murders. While he is able to wash away the blood from his ax, the bloodstained sock cannot be cleansed. The indelible grotesqueness of this sock symbolizes Raskolnikov's deepest guilt. Its heinousness is a constant reality which literally clings to him (even when asleep) with harrowing nearness.