Question

My father-in-law, may he live long, is what would be called a “broken tablet.” At one period in his life he was meant to become a “great man” in his sub-sector, and his community reached impressive achievements; even the leading rabbis of that circle presented him publicly as someone holy to behold. Over the years, though, he went through delays and setbacks and did not attain the greatness he was worthy of.
He is humble, occupied with his studies and his own affairs, and is almost not bitter about it.
In recent years, according to him (I haven’t seen it myself, but that proves nothing), he started watching Channel 14. One year passes and it already becomes like a commandment for him, and ever since then, whenever he comes to stay for Sabbaths and holidays, he spits poison and baseless hatred, even toward his grandchildren and everyone around, because they do not recognize Netanyahu’s messiahship, etc. He pins lies and slanders on the Jewish people in general who don’t watch Channel 14, and it has become oppressive. All the children flee the Sabbath table when he arrives, and the atmosphere turns grim.
Not inviting him is also problematic, because he is a lonely man, and of course he has no one else. On the other hand, when he comes he sows poison, dispute, sadness, and hatred, also toward us, because we do not believe in Netanyahu’s messiahship and on the contrary see flaws and dangers in his conduct.
 
What should we do?