Leviticus 13:55
And if, after the mark has been washed, the priest sees that the colour of it is not changed and it is not increased, it is to be burned in the fire: the disease is working in it, though the damage may be inside or outside.
Ezekiel 24:13
As for your unclean purpose: because I have been attempting to make you clean, but you have not been made clean from it, you will not be made clean till I have let loose my passion on you in full measure.
Hebrews 6:4-8
As for those who at one time saw the light, tasting the good things from heaven, and having their part in the Holy Spirit,
2 Peter 1:9
For the man who has not these things is blind, seeing only what is near, having no memory of how he was made clean from his old sins.
2 Peter 2:20-22
For if, after they have got free from the unclean things of the world through the knowledge of the Lord and Saviour Jesus Christ, they are again taken in the net and overcome, their last condition is worse than their first.