The second century hegira was a tumultuous year for Islam and the Islamic society. Bani Umayyah (the Umayyad), the real threats to the world of Islam, was on the verge of collapse and the Abbasid reign was to be launched with dark manners worse than the Umayyad. At such a critical time, a man of the Infallible Imams hoisted the flag of Islam, relied on his Imamate and knowledge to remove the dust of ignorance and tell the people that Islam was not the one echoed by the those who controlled power, wealth, hypocrisy and lust. He summoned the sparse and scattered but eager hearts to listen to him thus creating a chance to revive Islam and Islamic theology. He interpreted the Holy Qur'an as it was sent. He served Islam through two ways: teaching Islamic sciences and presenting Islamic models. The fact that Shia sect is also called Jafari sect is because of these two approaches.
Imam Sadiq (A.S) brought to the public the realities that were novel those days. The past and present of Islamic culture and civilization owe mush to the achievements of Imam Sadiq (A.S). Muslims owe the 3rd and 4th H. century's progress and developments to the illuminating teachings of Imam Sadiq (A.S). This does not mean that the endeavors and achievements of the previous Imams were less effective or less valuable. Rather, we mean that at his time everything was prepared for dissemination of the realities of Islam and Islamic law. Such a chance was not available to other Imams and Imam Sadiq (A.S) did his best to make optimal use of the chance.
The most outstanding achievement of Imam Sadiq (AS) was revival of the Shia school of thought, consolidating the principles and preferences of this school of thought and establishing discipline and order in this system of thought. This is why Jafari sect is also named Alavi sect, Husseini sect, and Sajjadi sect as well.
source : www.tebyan.net
