What are some oxymorons that are in fahrenheit 451

Read the excerpt below and answer the question. 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 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. in at least 100 words, explain what jefferson says here about the revocability of laws and what that means for his virginia statute for religious freedom.