To Democratically Repeal Natural Right?

The question Orin Kerr asked and Timothy Sandefur answered. I like Mr. Sandefur's answer. But he could have quoted the end of Thomas Jefferson's Statute on Religious Freedom. You see this was no "ordinary" statute:

III. And though we well know that this assembly elected by the people for the ordinary purposes of legislation only, have no power to restrain the acts of succeeding assemblies, constituted with powers equal to our own, and that therefore to declare this act to be irrevocable would be of no effect in law; yet we are free to declare, and do declare, that the rights hereby asserted are of the natural rights of mankind, and that if any act shall be hereafter passed to repeal the present, or to narrow its operation such act will be an infringement of natural right.