'Foul' in the Bible

There was a man in the synagogue who was possessed by the spirit of an unclean demon; and he cried out with a loud and terrible voice,

They were all astonished and in awe, and began saying to one another, “What is this message? For with authority and power He commands the unclean spirits and they come out!”

And the people from the towns in the vicinity of Jerusalem were coming together, bringing the sick and those who were tormented by unclean spirits, and they were all being healed.

For unclean spirits (demons), shouting loudly, were coming out of many who were possessed; and many who had been paralyzed and lame were healed.

But actually, I have written to you not to associate with any so-called [Christian] brother if he is sexually immoral or greedy, or is an idolater [devoted to anything that takes the place of God], or is a reviler [who insults or slanders or otherwise verbally abuses others], or is a drunkard or a swindler—you must not so much as eat with such a person.

Do not let unwholesome [foul, profane, worthless, vulgar] words ever come out of your mouth, but only such speech as is good for building up others, according to the need and the occasion, so that it will be a blessing to those who hear [you speak].

So the first angel went and poured out his bowl on the earth; and loathsome and malignant sores came on the people who had the mark of the beast and who worshiped his image.

There will no longer exist anything that is cursed [because sin and illness and death are gone]; and the throne of God and of the Lamb will be in it, and His bond-servants will serve and worship Him [with great awe and joy and loving devotion];