The era of Imam Baqir (as) came to an end and the Imamate of Imam Sadiq (as) began in 114 hijra, continuing until 148. Imam Sadiq's (as) era may be divided into two stages: the first stage, 114 to 132 or 135 hijra, is an era of relief and opening up of the political atmosphere. It continues until the rise of the Abbasside or the Caliphate of Mansur.
During this first period, due to the feud of the Umayyad between themselves, the infallible Imams found an opportunity to impart the teachings of the Shiites. This characteristic is peculiar to this period. It did not exist during Imam Baqir's (as) era, rather it was the hey-day of the Umayyad, and Hisham ibn (son of) Abdul Malik, who was the greatest Umayyad personality after Abdul Malik, was in power.
Therefore there were no quarrels in the ruling party so that Imam Baqir (as) could take the opportunity to get favorable results. The civil wars and political clashes belong to the early years of Imam Sadiq's era when the Abbasside's call gradually began to spread. At the same time it was the peak of the call of Alawi Shiism throughout the world.
When Imam Sadiq (as) began his Imamate, there were a number of internal feuds and civil wars in the world of Islam in Africa, Khurasan, Fars, Mesopotamia, and other places and the Umayyad faced great problems. The three tasks Imam Sajjad (as) had undertaken (mentioned before), that is, imparting the Islamic teachings, the issue of Imamate and stressing the Imamate of the Progeny of the Holy Prophet (Ahl-ul-Bayt (as)) became very transparent during the life of Imam Sadiq (as).
For instance, Amr ibn abi al-Meqdam narrates: "I saw Imam Sadiq (as) standing among the people in Arafat on the day of Arafa in Hajj ceremony. Addressing the people on his front, then on his right side, then on his left, and his back, he was repeating the following sentence on each side for three times: Verily, the Messenger of God was in fact the Imam; after him it was Ali ibn Abi Talib; after him Hassan, after him Husayn, after him Ali Ibn al-Hussein (Sajjad), after him Muhammad Ibn Ali, and after him I am the Imam.' The Imam repeated this sentence twelve times."
Bear in mind that using the world "Imam" was very sensitive, for it put to question the legitimacy of those caliphs who were in power.
Another tradition states: "A person coming from Kufa to Khurasan was inviting the people to accept the rule (Wilayah) of Ja'far ibn Muhammad (Imam Sadiq as)."
Just see, in Iran, when could we announce that we were establishing an Islamic Republic in our struggles? Throughout the years of combat, maximum that we could announce was to explain the Islamic viewpoints about the government, that is, the criteria and conditions set by Islam for the government and rulers. This was what we could say in this regard.
The ground was not at all prepared for claiming the establishment of an Islamic government or naming a particular person as the ruler. It was in 1978 or 1979 that we could discuss the issue of Islamic government as a particular claim in our private parleys, but we could not name the ruler.
However, Imam Sadiq's (as) friends go to various parts of the Islamic country and invite the people to accept his rule. What does it mean? Does not it mean that the promised time has come? This is the very year 140 Hijra, which was mentioned before. This situation was created as a natural consequence of the movement of the infallible Imams, heralding the establishment of an Islamic government.
Today, we comprehend the concept of "Wilayah" very well. Earlier, Wilayah was interpreted as sympathy and love. People were invited to accept the Wilayah of Ja'far ibn Muhammad (as). If Wilayah is interpreted as love, it is not necessary to invite the people to accept the love of Ja'far ibn Muhammad.
Moreover, if we interpret Wilayah as love, the second part of the above-mentioned tradition does not make sense. Just pay attention to the second part of the tradition: " one group accepted and obeyed the Wilayah of Imam Sadiq (Ja'far ibn Muhammad AS); and another group rejected it."
Who could reject love for the Progeny of Prophet of Islam in the world of Islam? In the continuation of the tradition, we read, " Yet, another group expressed reservation, and showed restraint to this Wilayah." Reservation and restraint are not compatible with love. This indicates that Wilayah means something else; it means government and rule. And then some of them came to the Imam and discussed the issue. Addressing one of those who had expressed reservation, the Imam said, "Coming to the matter of Wilayah you pretend to be conservative and express reservation, however, if you are such conservative why did you commit such and such sin (raping) on the side of such and such river on such and such day?" This clearly indicates that the Imam acknowledged the person who was inviting the people in Khurasan, or probably he had been a messenger of Imam.