Sunni Jurisprudence
The Sunni follow any one of four major schools on jurisprudence founded by imams ibn Hanbal, abu Hanifa, Malek, and el-Shafei, scholars of the ninth to eleventh centuries. These schools, referred to respectively as the Hanbali, Hanafi, Maliki, and Shafei, are followed by different Muslim states either entirely or in part. Egypt is traditionally Maliki. Saudi Arabia is traditionally Hanbali, although the country follows more closely the teachings of imam Muhammad Abdal-Wahab, a Hanbali reformer of the early 1800's. Even though there are differences in interpretation of the Sharia among these authorities, they are all recognized as valid.
In its most glorious period, from the seventh to the thirteenth centuries, Islam produced a legal system founded on scientific knowledge and nurtured by a faith that has endured the test of time. But during that period it was ijtihad (progressive reasoning by analogy) which produced the most far-reaching developments. Reformers like ibn Taymiyah (late 1200's) was one of many great jurist-philosophers who opened new horizons in the knowledge and understanding of Islam's application to the needs of society. But in the twelfth century, ijtihad was pronounced ended by some theologians of the time. They argued that all was to be known was known. Consequently, Islamic jurisprudence became somewhat stagnant until its contemporary resurgence under the aegis of Al-Azhar scholars and other modern reformers of the last two centuries, such as al-Ghazali, al-Afghani, and Muhammad Abdu. Contemporary jurisprudential developments continue the work begun in past ages, meeting individual requirements and collective demands for resolving the problems and conflicts of modern life, while remaining compatible with Islam.