Posting religious beliefs in a science based discussion will never go down well.

No, but it's commonly downvoted. Posting about the technology alone would attract a better response here.

It's best not to react to the first hour of voting, let the masses even it out.

Commenting about downvoting is against the guidelines. https://news.ycombinator.com/newsguidelines.html

Content doesn't have to be against rules to be downvoted. I disagree with the opinion in it, so I downvote. It has nothing to do with rules.

Maybe it's just me, but I reserve downvotes for trolling, intentionally misleading, flamebaiting, or off topic posts. If I see something I disagree with, I'll post a response instead of downvoting (as I am in this case). Downvoting purely because you disagree, especially without a rebuttal, is simply censorship.

He didn't say his belief is the only right one. It did contribute to the conversation for some of us. And I agree with a sibling commenter, downvoting should ideally be reserved for non-serious/troll comments?

If someone mentions they like a food or a movie or a song that you don't like, do you downvote?

Depends how it's phrased. If someone says "I like liquorice" then I'm not going to downvote. But if someone said "liquorice is the best food in the world" as if it was a fact, then I am going to downvote. If OP said "It is my opinion that Jupiter was created by god" I would not have downvoted. But it's his stating it as a fact which is making me downvote.