I was given a very specific (but non-inclusive) list of people I was not allowed to bring home. That included any and all women, naturally, but also included any and all men of any colour darker than germanic-european-white, and indeed any men of a religion other than young-earth-creationists.

Breaking any of these rules while still living in the house would have meant my expulsion from the house. I'd like to say my mom wouldn't have allowed him to kick me out but I really don't know.

My parents thought/think I’m gay because I’ve never had a girlfriend.

Conservative rural Christianity. It's fine to be gay as long as no one ever knows about it.

Once saw something saying that all of the Christian "it's fine if you want to choose to be gay, just don't do it in my face" rhetoric is code for:

"you should be ashamed of being gay, because bring gay is a sin. You should commit sin hidden behind closed doors just like we do, when our priests grope children and husbands cheat on their wives."

Turn it off, like a light switch

There, it's gone

My hetero side just won

I'm all better now

Boys should be with girls, that's Heavenly Father's plan

So if you ever feel you'd rather be with a man,

Turn it off!

"Well, I think it's okay that you're having gay thoughts, just so long as you never act on them"

No, 'cause then you're just keeping it down

Like a dimmer switch on low, thinking nobody needs to know

But that's not true!

Being gay is bad but lying is worse

So just realize you have a curable curse,

And turn it off!

It's much funnier to accuse them of being closeted as it drives them nuts.

The most vocal homophobes probably aren't mostly a 0 on the Kinsey scale even if they're heterosexual given 0s probably are not the majority. Especially the kind who act like it's something that's okay if you hide it or think you can just turn it off, as described in OP's case.

Calling a 1 "gay" is obviously misleading, but from the perspective of many homophobes those occasional thoughts are problematic.

And you've also given your homophobic dad more reason to be homophobic

No, but in very narrow circumstances, controlled violence to back down continued abuse does work wonders.

People will only bully and abuse people they think they can get away with it towards. I'm those cases, controlled violence is an effective tool because it draws a firm boundary and expresses the consequences for crossing it.

Someone behaving like the "dad" in the story posted is only doing it because they think they can get away with it. That kind of person is very likely to back the fuck off when the son backs them the fuck off. Remember, they're already using the threat of violence in the posted scenario. The only realistic response to a threat of violence, when outside assistance via legal recourse isn't available, is shutting them the fuck down hard and fast.