It sounds like something on the spectrum (it could be bipolar, schizophrenia, or something similar - only a psychiatrist can tell for sure.
Try to get him to go with you to see a psychiatrist or psychologist - find something that he can agree with you to see him about - it might be sleep issues, or stress, or anxiety or depression or not feeling good… just get him in there, prewarn the psychiatrist and share a much as you can with the psychiatrist before hand.
Here are some resources - do you have other family members that can help you. Educate everyone, and keep a journal about your brother’s behaviors and beliefs so that you can share it with the mental health professionals.
Study this document:
FIRST Aid for Psychosis
http://www.schizophrenia.com/sznews/archives/005561.html
How to get help:
Here is a good place to get your father to, if you can:
I recommend you watch these videos:
I Am Not Sick, I Don’t Need Help! - Dr. Xavier Amador - Pt. 1
and
I Am Not Sick, I Don’t Need Help! - Dr. Xavier Amador - Pt. 2