'Unclean Spirit' in the Bible

And fear came upon them all, and they were talking together to one another, saying, What word is this? because with authority and power He commands the unclean spirits, and they come out.

and those troubled by unclean spirits; and they were getting healed.

For He commanded the unclean spirit to come out from the man; for since a long time he had possessed him, and he was frequently bound, secured with chains and fetters, and smashing his bonds, was driven by the demons into the desert.

And he yet coming, the demon dashed him down and convulsed him. And Jesus rebuked the unclean spirit and healed the child, and gave him to his father.

When the unclean spirit may go out from the man, he goes through dry places; seeking rest, and finding none, he says, I will return into my own house, whence I came out.