If you are not living at home, than I would make it a point to NEVER speak with your father again, he showed who he is loyal too and its a poublishing company cult, and not god. He is disloyal to you and I wiould let him know about it and then cut him out of your life, but then again I am a bit extreme. But family ties should never be broken especially by the family.
Don't let them ram rod you at the JC either. They will want to discuss only what they want too and then expect you to comply with their wishes. Do as a friend of ours did, when they insisted on not letting him get his points across he told them to get the effing hell out of his house and don't come back send a letter announce anything about him or he will sue their ass, and if that doesn't work well then there are other methods.
He hasn't had a visit from any of them for over 5 years now.