Holding to Rulings Based on Custom...
In an important work of law, judicature and governement, the great Egyptian jurist of the Maliki school, Shihab al Din al Qarafi (d.684/1285) is asked the following question:
What is the correct view concerning those rulings found in the madhhab of al-Shafi, Malik and the rest, which have been deduced on the basis of habits and customs prevailing at the time these jurists reached these conclusions? When these customs change and the practice comes to indicate the opposite of what it used to, are the fatwas recorded in the manuals of the jurists rendered thereby defunct, it becoming incumbent to issue fatwas based on the new custom? Or is it to be said, we are mere followers of the independent, authoritative jurists. It is thus not our place to innovate new rulings, as we lack the qualifications to do so. We issue, therefore, fatwas according to what we find in the books handed down on the authority of the independent, authoritative jurists"?
In his answer, al-Qarafi emphatically affirms that a ruling remains valid only as long as the custom or circumstances on which it was based remains intact and retains the same implications it had at the time the ruling was originally reached. Thus, he responds:
Holding to rulings that have been deduced on the basis of custom, even after this custom has changed, is a violation of consensus (ijma) and an open display of ignorance of the religion.
[Quoted from an article by Shaykh Abdal Hakim Jackson]