'Unclean Spirit' in the Bible

And amazement came upon all; and they were talking together, one with another, saying, "What is this word, that with authority and power He commandeth the unclean spirits, and they come out!"

and those troubled with unclean spirits were being healed;

For He was commanding the unclean spirit to come out from the man; for many times had it seized him, and he was bound with chains and fetters, kept under guard; and, bursting the bonds, he was driven by the demon into the deserts.

And, while he was yet coming, the demon thrust him down, and greatly convulsed him. But Jesus rebuked the unclean spirit, and healed the boy, and gave him back to his father.

"When the unclean spirit goes out from the man, it passes through waterless places, seeking rest; and, not finding it, it says, 'I will return into my house whence I came out.'