Jesus Accused Judas of Slander!

On the evening he was betrayed and immediately after the evening meal, Jesus had washed the disciples’ feet, he announced that they were spiritually clean, except for one of them (John 13:10-11). Judas was unclean, spiritually. What does this mean? For a few days now I have been looking at Judas’ heart. His loyalty to Jesus was divided by his commitment to a cause, presumably a political cause, so Judas was probably a Zealot or a member of a similar political group.