Philosophy of Torah financial law

Good evening!
There is a section of the Rishonim on whether the ownership of a rabbinate is beneficial to the Torah, and my question is that in the Shabash the concept of 'ownership' was applied metaphysically and ontologically, so it was understood that by the ownership of a rabbinate this does not happen, but to the extent that 'ownership' this year is only a legal relation (and especially for the Gersh, whose ownership laws today are a category prior to the laws of the Torah), then it is difficult for me to say that it matters how we determined this relation and the rabbinate is the owner?
And to illustrate the absurdity of this, I will give an example in a case where the seller regretted the sale after the purchase. Is it conceivable that the buyer would commit theft according to Torah law (of course, if the person were not a thief in the 14th century, and if the law of the Hararash regarding theft were not the same)?
Thank you very much!