“Then goeth he, and taketh with himself seven other spirits more wicked than himself, and they enter in and dwell there: and the last state of that man is worse than the first. Even so shall it be also unto this wicked generation.”
Matthew 12:45 — Greek Interlinear
Church Fathers on Matthew 12:45
The Lord had said to the Jews, 'The men of Nineveh shall rise in the judgment with this generation, and shall condemn it;' that they should not therefore be careless, He tells them that not only in the world to come but here also they should suffer grievous things; setting forth in a sort of riddle the punishment that should fall upon them whence He says, 'When, the unclean spirit has gone out of a man.'
Some suppose that this place is spoken of heretics, because the unclean spirit who dwelt in them before when they were Gentiles, is cast out before the confession of the true faith; when after they went over to heresy, and garnished their house with feigned virtues, then it is that the Devil, having taken to him other seven evil spirits, returns and dwells in them; and their last state becomes worse than their first. And indeed heretics are in a much worse condition than the…
He calls the hearts of the Gentiles, 'dry places,' as lacking all the moisture of wholesome waters, that is of the holy Scriptures, and of spiritual gifts, and strangers to the pouring in of the Holy Spirit.