Into space? Who believes this?
Nobody. They believe heaven is up. The logical extrapolation is up into space. To point that out is to mock the imagery.
If people are talking what sounds like crazy shit, and you try to highlight that by reflecting back at them how it sounds like crazy shit, then going "You're mocking what sounds like crazy shit!" doesn't fix how it sounds like crazy shit.
There are no details to give; this is not something that either scripture nor tradition have much to say on...
Well, see, that's something to think about. Belief in other realms seems to always require being content with few details.
When I was a little kid, a preacher was going on about the roof flying off the church someday and all the congregation flying up and out. I looked up and wondered if the roof had hinges to help that happen; it wasn't skepticism but my curiosity. I later, as a teen, lost my mind and stopped the questioning, for a while, and held the vague belief (up and out of this dark world) without thinking it through in detail anymore. But then I regained my mind and realized that's crazy shit.
The problem's still there. People think heaven is up and out of the world into somewhere better than earthly reality. If that can be made into something sensible, allegorically, then tell it to the Christians.
And don't get us started on the Bible.
Who is "us"? And in a post yesterday you were talking on behalf of "we" Christians.
Correct me if I'm wrong, but I seem to remember you saying you're an atheist Wiccan Christian?
Born in another time, you'd have been burned at a stake if they found out how heretical you are. So why do you present yourself as representative of Christians? Is it your opportunity to show how sophisticated this stuff COULD BE in the hands of people other than Christian fundies? If so, that's going to take details.
It's possible a few Christian mystics weren't just driven crazy by a mix of fervor and austerities. Though, as Sam Harris remarked, on the occasions some Christian contemplatives start making sense, they sound
less like Christians and more like Buddhists (less stuff about the distant otherness, yet literalness, of heaven). But in the end, that argument is with the "most Christians" we've been discussing. Tell
them about an allegorical, a-historical, psychological understanding of their mythology.