John Lightfoot on Matthew 12:45

[So shall it be to this evil generation.] These words foretell a dreadful apostasy in that nation and generation.

I. It is something difficult so to suit all things in the parable aforegoing, that they may agree with one another: 1. You can hardly understand it of unclean spirits cast out of men by Christ; when through the whole evangelic history there is not the least shadow of probability that any devil cast out by him did return again into him out of whom he had been cast. 2. Therefore our Saviour seems to allude to the casting out of devils by exorcisms: which art, as the Jews were well instructed in, so in practising it there was need of dexterous deceits and collusions. 3. For it is scarcely credible that the devil in truth finds less rest in dry places than in wet: but it is credible that those diabolical artists have found out such kind of figments for the honour and fame of their art. For, 4. It would be ridiculous to think that they could by their exorcisms cast a devil out of a man into whom he had been sent by God. They might, indeed, with a compact with the devil, procure some lucid intervals to the possessed; so that the inhabiting demon might deal gently with him for some time, and not disturb the man: but the demoniacal heats came back again at last, and the former outrages returned. Therefore, here there was need of deceits well put together, that so provision might the better be made for the honour of the exorcistical art; as, that the devil, being sent away into dry and waste places, could not find any rest; that he could not, that he would not always wander about here and there, alone by himself, without rest; that he therefore returned into his old mansion, which he had formerly found so well fitted and prepared for him, &c.

Therefore these words seem to have been spoken by our Saviour according to the capacity of the common people, or rather, according to the deceit put upon them, more than according to the reality or truth of the thing itself; taking a parable from something commonly believed and entertained, that he might express the thing which he propounded more plainly and familiarly.

II. But however it was, whether those things were true indeed, or only believed and conceived so, by a most apt and open comparison is shown that the devil was first cast out of the Jewish nation by the gospel; and then, seeking for a seat and rest among the Gentiles, and not finding it, the gospel everywhere vexing him, came back into the Jewish nation again, fixed his seat there, and possessed it much more than he had done before. The truth of this thing appears in that fearful apostasy of an infinite multitude of Jews, who received the gospel, and most wickedly revolted from it afterward; concerning which the New Testament speaks in abundance of places.