The ummah's greatest achievement over the past millennium has undoubtedly been its internal intellectual cohesion. From the fifth century of the Hijra almost to the present day, and despite the outward drama of the clash of dynasties, the Sunni Muslims have maintained an almost unfailing attitude of religious respect and brotherhood among themselves. It is a striking fact that virtually no religious wars, riots or persecutions divided them during this extended period, so difficult in other ways.
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It was at that time, too, that the attitude of toleration and good opinion between the Schools became universally accepted. This was formulated by Imam al-Ghazali, himself the author of four textbooks of Shafi'i fiqh,[36] and also of Al-Mustasfa, widely acclaimed as the most advanced and careful of all works on usul, usul al-fiqh fil madhhab. With his well-known concern for sincerity, and his dislike of ostentatious scholarly rivalry, he strongly condemned what he falled ‘fanatical attachment to a madhhab’.[37] While it was necessary for the Muslim to follow a recognised madhhab in order to avert the lethal danger of misinterpreting the sources, he must never fall into the trap of considering his own school categorically superior to the others. With a few insignificant exceptions in the late Ottoman period, the great scholars of Sunni Islam have followed the ethos outlined by Imam al-Ghazali, and have been conspicuously respectful of each others madhhab. Anyone who has studied under traditional ulama will be well-aware of this fact.[38]
The evolution of the Four Schools did not stifle, as some Orientalists have suggested,[39] the capacity for the refinement or extension of positive law.[40] On the contrary, sophisticated mechanisms were available which not only permitted qualified individuals to derive the Shariah from the Quran and Sunnah on their own authority, but actually obliged them to do this. According to most scholars, an expert who has fully mastered the sources and fulfilled a variety of necessary scholarly conditions is not permitted to follow the prevalent rulings of his School, but must derive the rulings himself from the revealed sources. Such an individual is known as a mujtahid,[41] a term derived from the famous hadith of Muadh ibn Jabal.[42]
Few would seriously deny that for a Muslim to venture beyond established expert opinion and have recourse directly to the Quran and Sunnah, he must be a scholar of great eminence. The danger of less-qualified individuals misunderstanding the sources and hence damaging the Shariah is a very real one, as was shown by the discord and strife which afflicted some early Muslims, and even some of the Companions themselves, in the period which preceded the establishment of the Orthodox Schools. Prior to Islam, entire religions had been subverted by inadequate scriptural scholarship, and it was vital that Islam should be secured from a comparable fate.
~Abdal-Hakim Murad