'Unclean' in the Bible

In the synagogue there was a man possessed by the spirit of an unclean demon, and he cried out with a loud voice,

And amazement came upon them all, and they began talking with one another saying, “What is this message? For with authority and power He commands the unclean spirits and they come out.”

who had come to hear Him and to be healed of their diseases; and those who were troubled with unclean spirits were being cured.

For He had commanded the unclean spirit to come out of the man. For it had seized him many times; and he was bound with chains and shackles and kept under guard, and yet he would break his bonds and be driven by the demon into the desert.

While he was still approaching, the demon slammed him to the ground and threw him into a convulsion. But Jesus rebuked the unclean spirit, and healed the boy and gave him back to his father.

“When the unclean spirit goes out of a man, it passes through waterless places seeking rest, and not finding any, it says, ‘I will return to my house from which I came.’