Just a point about your hypothetical. It does nothing to distinguish between genuine foolishness and spiritual truths. I think that we would both agree that the Flat Earther's are simply foolish, not "spiritual"
In fact I would say that it is hard to judge ideas about the history and operation of the physical universe as "spiritual truths" - indeed they would seem to be natural truths by definition.
And is a literal reading of the Bible really the best way to extract spiritual truths ? Wouldn't a preference for literalism be more likely a mark of a "natural mind".
Now if you want to look for spiritual truths perceived as foolish be the world, how about loving your enemies ? Giving all you have to the poor? Choosing to live in poverty, trusting God to provide ?
quote: ahhh yes. faith without works is dead. You might even argue that we don't need the book, but I believe that scripture is alive and is profitable for humans...and I might point out that some folks could give all that they had materialistically and yet hold back their heart. Anyhow lets continue...
I think that you might be missing the larger point. Those ideas ARE all Christian teachings, relating to spiritual values ("storing up treasure in heaven") that ARE widely seen as foolish. And yet it makes sense that they at least COULD be spiritual truths or based on spiritual truths.
This is not so for, say, Young Earth beliefs which seem to differ from Flat Earth beliefs only in that the evidence against them is a little less obvious.