Meaning is culturally contingent, though - the appropriate “moral” of a parable can change as culture changes around it, which can lead to changes to the parable itself.
For a contrived example, 100 years ago, the idea that one would defy one’s parents and pursue one’s own dreams would have been frowned upon, and any parables referencing that action would clearly contain the moral that one should listen to one’s parents. Today, that would be an almost unthinkable moral - discard your dreams and stick to whatever hidebound business your parents were in? Surely we got something wrong in the translation here.
Written in meter, though, clearly the only word that fits here is “shan’t”, not “must”.
I bet you've not seen a mustard seed, but you still get what is being said, in the parable of the mustard seed.
If the parable is talking to a foundational reality, rather than cultural situations, I think it can endure.
I get what you are saying, but even parables don't have 'the truth'. I would imagine that there may even be parables that argue the opposite position. And both, opposing positions could be right, depending on the context.
For a contrived example, 100 years ago, the idea that one would defy one’s parents and pursue one’s own dreams would have been frowned upon, and any parables referencing that action would clearly contain the moral that one should listen to one’s parents. Today, that would be an almost unthinkable moral - discard your dreams and stick to whatever hidebound business your parents were in? Surely we got something wrong in the translation here.
Written in meter, though, clearly the only word that fits here is “shan’t”, not “must”.