With reference to your answer here.
I’m wanting to learn, in the light of the principles of four Sunni schools, to what extent can rulings change? What part of the rulings are unchangeable and what is changeable with time/place ? How is this possibility of change not subject to the verse that ascribed shirk to Jews for their making of halal what Allah made haram and vice versa ? Would the consequence of using qiyas to oppose what is allowed in Quran, sunnah and unanimous agreement for years, as in the case of banning slavery, create any new principle in Islamic law or is it completely within the bounds of the traditional principles of the four schools ? Does the end of slavery call for reflection by traditionalist and conservatives in their non-flexible approach to the modern world or modernism?
Question refers to issues of principles of jurisprudence. For example syasa shar’iyya (governance issues) can be modified at will by the ruler, and he can also temporarily make obligatory or prohibited certain acts which usually do not have such a status. You will need to study that formally or ask a specialized website.
Hajj Gibril Haddad