Shufah is an excellent example of the continuity of an Islamic institution and of the capacity of that institution for change. Although it is not, strictly speaking, a part of personal status law, which is said to be the only part of Islamic law that is being applied in Islamic countries, it has survived in a recognizable form. Islamic countries, in their attempts at law reform, have effected little change in the traditional law of personal states, only after heated discussions and controversy. On the other hand, profound changes were introduced into the traditional law of preemption with little controversy. The difference in the attitude of law reformers to change in these two areas might be attributable to the fact that rights in personal status law were considered by the jurists the very heart of Islamic law and, therefore, sacrosanct, while the right to preemption was considered a "weak right" and, therefore, more amenable to change.
Farhat J. Ziadeh, Shufcah: Origins and Modern Doctrine, 34 Clev. St. L. Rev. 35 (1985-1986)