The Catholic Church?
I’ve just noticed that there is a pattern of not admitting you need help until something disrupts your normal functioning enough that you realize ‘god, I need to get help’. For one bipolar guy I know, it was sitting in jail for three days at the end of a wild Miami vacation - he realized jail wasn’t the place for him, came home, got sober through NA, went on meds, and went to nursing school. For my friend, it was basically his entire life and identity disintigrating. Unfortunately it seems more likely to be something more extreme than yelling at your girlfriend or whatever, when bipolar disorder is involved. Just IME. It makes sense when you have frequent mania and delusions of grandeur that waking up next to a hooker isn’t going to make much of an impression.
Have you considered getting a Rogers Order, at least for a year or two?
There really isn’t any “convincing” someone who is manic to take meds. Usually they need to be hospitalized to get to that place.
Outside of that, I’d try to get him engage in a conversation about things important to him and things folks think are important for him and see if there’s a middle ground and how he’d get there.
Another thing to try would be getting him involved with peer recovery movement, such as Recovery Learning Centers, Hearing Voices groups, etc. These can be very helpful in getting someone into recovery mode.