Jaʿfar b. Muhammad b. ʿAli b. al-Husayn (a) (Arabic: جعفر بن محمد بن علي بن الحسین), (b. 83/702 – d. 148/765) known as Imam al-Sadiq (a) (الإمام الصادق), is the sixth Imam of Imamiyya and the fifth Imam of Isam'ilis. His Imamate lasted 34 (lunar) years (114/733 - 148/765) and was concurrent with the reign of the last five Umayyad caliphs (that is, from Hisham b. 'Abd al-Malik onwards) and with that of the first two Abbasid caliphs, al-Saffah and al-Mansur al-Dawaniqi. Because of the weakness of the Umayyad rule at his time, Imam al-Sadiq (a) was able to have relatively wider scholarly activities. His companions, students, and those who quoted hadiths from him is said to have amounted to four-thousand people. Most of the hadiths of Ahl al-Bayt (a) recorded in Twelver Shiite hadith collections are from Imam al-Sadiq (a). This is why Imamiyya is called Ja'fari School. Imam al-Sadiq (a) has had a high status in the eyes of prominent Sunni scholars. Abu Hanifa and Malik b. Anas were among the people who quoted hadiths from him.
Despite the weakness of the Umayyads and the requests from the Shi'a, Imam al-Sadiq (a) did not rise up against the caliphate. He rejected Abu Muslim al-Khurasani and Abu Salama, who asked him to become the caliph. He did not take part in the revolt of his uncle Zayd b. 'Ali either and discouraged the Shi'a from getting involved in any uprisings. However, he did not have good relations with the caliphs of his time either, and he had to do taqiyya because of their persecution.
To facilitate his contacts with the Shi'a, Imam al-Sadiq (a) established the network of wikala (deputyship). The activities of this network continued and increasingly expanded until the end of the Minor Occultation. During Imam al-Sadiq's (a) time, the Ghulat became very active. The Imam (a) vehemently opposed them, declaring them infidels or polytheists.
The Imam (a) was summoned several times to Baghdad, and thus he traveled to Iraq and also visited Karbala, Najaf, and Kufa. He showed the grave of Imam Ali (a), which was previously unknown, to his companions.
Some Shiite scholars believe that Imam al-Sadiq (a) was poisoned by al-Mansur al-Dawaniqi and thus martyred. He introduced Imam al-Kazim (a) to his companions as his successor, but to protect the life of Imam al-Kazim (a), he mentioned in his will five people, including al-Mansur, as the executors of his will. After the martyrdom of Imam Al-Sadiq (a), several sects appeared among the Shi'a, including Ismailis, Fatahiyya, and Nawusiyya.
Ja’far b. Muhammad b. ‘Ali b. al-Husayn b. ‘Ali b. Abi Talib (a) was the sixth Imam of Imamiyya and the fifth Imam of Isma’ilis. His father was Imam Muhammad al-Baqir (a). His mother was Umm Farwa the daughter of al-Qasim son of Muhammad b. Abi Bakr. According to the report of Kashf al-ghumma from a sunni scholar, Imam al-Sadiq (a) is reported to have said, “Abu Bakr begot me twice”, because the Imam’s (a) mother was a descendant of Abu Bakr both from her mother’s and her father’s sides. However, some scholars such as Allama Shushtari and al-Allama al-Majlisi do not consider this hadith authentic.
His famous Teknonym (kunya) was Abu ‘Abd Allah (because of his second son, ‘Abd Allah al-Aftah). In some sources, other Teknonyms such as Abu Isma’il (because of his eldest son, Isma’il) and Abu Musa (because of his son Musa al-Kazim (a)) are mentioned.
His famous title was al-Sadiq (الصادق) which means “truthful”. According to a hadith, the Prophet (s) gave this title to Imam (a) to distinguish him from Ja’far al-Kadhdhab. However according to an analysis of the history, Imam al-Sadiq (a) was titled “al-Sadiq” because he (a) avoided any involvement in the uprisings of his time; for at that time, the one who gathered people around and provoked an uprising against the government was titled Kadhdhab (the liar). At the time of Imams this title was used for him (a). Some Sunni scholars such as Malik b. Anas, Ahmad b. Hanbal, and al-Jahiz have mentioned the Imam (a) by this title.
Other titles have also been mentioned for Imam (a) including al-Sabir, al-Tahir, and al-Fadil.
He was born on Rabi’ I 17, 83/April 20, 702 in Medina. Some historians and biographers have mentioned his birth in 80/699. Twelve years of his life were contemporary with his grandfather and thirty one years of it were contemporary with his father and his imamate lasted thirty four years.
|Hamida||daughter of Sa’id or Salih||Musa, Ishaq, Muhammad||Musa al-Kazim (a) is the seventh imam of Twelver Shi’as|
|Fatima||daughter of al-Husayn b. ‘Ali b. al-Imam al-Husayn (a)||Isam’il, ‘Abd Allah, Umm Farwa||‘Abd Allah claimed imamate after the demise of Imam al-Sadiq (a) and his followers are known as Fatahiyya. Isma’il died in the lifetime of his father, but a group did not accept his demise and were named Isma’ilis.|
|other wives||–||‘Abbas, ‘Ali, Asma’, Fatima|
The life of Imam al-Sadiq (a) coincided with the reign of the last ten Umayyad caliphs, including ‘Umar b. ‘Abd al-‘Aziz and Hisham b. ‘Abd al-Malik, and the reign of the first two Abbasid caliphs, al-Saffah and al-Mansur al-Dawaniqi.
During Imam al-Sadiq’s (a) imamate, the Umayyad rule started to decline and eventually collapsed, and then the Abbasids acceded to power. The weakness of the rulers created a good opportunity for the Imam (a) to engage in scholarly activities. This relatively free environment existed only in the third decade of the second/eighth century; the Imam (a) and his followers were under great pressure before that under the Umayyads and also after it because of the revolt of Muhammad al-Nafs al-Zakiyya and his brother Ibrahim. 
Proofs for Imamate
Several people have narrated from Imam al-Baqir (a) about the imamate of his son, Ja’far, among whom are Hisham b. Salim, Abu l-Sabah al-Kanani, Jabir b. Yazid al-Ju’fi and ‘Abd al-A’la mawla Al Sam.
Al-Shaykh al-Mufid wrote that “In addition to the Imam al-Baqir’s (a) will about the imamate of his son Ja’far, his superiority and merits in knowledge, piety, and practice over all his brothers, cousins and all other people of his time prove his imamate.”
Since the Shia were scattered in different parts of the Muslim territories and it was difficult for them to be directly in touch with the Imam (a), Imam al-Sadiq (a) appointed a number of representatives (wakil) for different regions, who were responsible to transfer the khums, zakat, and donations of the Shia to the Imam (a) and also to take their questions and messages to the Imam (a) and the Imam’s (a) response back to them.
The network of representatives, which continued its function until the death of ‘Ali b. Muhammad al-Samuri, the fourth representative of Imam al-Mahdi (a), is sometimes referred to as the wikala network.
At the time of Imam al-Baqir (a) and Imam al-Sadiq (a), the Ghulat expanded their activities. They believed that the Imams were gods or prophets. Imam al-Sadiq (a) strongly rejected these ideas; he prohibited his followers from interacting with the Ghulat and proclaimed them infidels and polytheists. According to a hadith, the Imam (a) said: “Do not socialize with them; do not eat, drink, or shake hands with them.” The Imam (a) warned: “Be careful lest the Ghulat corrupt your youth. They are the worst enemies of God. They belittle God, but attribute lordship to God’s servants.”
Because of the weakness of the Umayyads at the time of Imam al-Sadiq (a), the Imam was relatively free to teach and engage in scholarly activities. This religious and scholarly freedom rarely happened during the time of the other Imams, and thus most of our hadiths are from Imam al-Sadiq (a). According to Ibn Hajar al-Haythami, people learned and transmitted a great deal of knowledge from him, and his fame reached far and wide. Al-Jahiz also wrote that “his knowledge and jurisprudence have filled the world.” Al-Hasan b. ‘Ali al-Washsha’ reports that he saw nine-hundred people in the mosque of Kufa transmitting hadiths from Imam al-Sadiq (a).
Most of the Shiite hadiths, whether in fiqh or theology, are from Imam al-Sadiq (a), and the number of the people who transmitted hadiths from him (4000, according to al-Irbili) is greater than the number of hadith transmitters from any other Imam. According to Aban b. Taghlib, the Shia would refer to the words of Imam Ali (a) when they disagreed about a saying of the Prophet (s) and would refer to the sayings of Imam al-Sadiq (a) when they disagreed about Imam Ali’s (a) words.
Because of the significant role of Imam al-Sadiq (a) in the elaboration of Islamic teachings, Twelver Shiism is often called Ja’fari School and the Imam (a) is known as its head.
In Shiite hadith collections, some dialogues or debates between Imam al-Sadiq (a) and theologians of other schools and some atheists are reported. In some of these debates, the Imam’s (a) students debated and the Imam (a) oversaw the debate and sometimes engaged in it. For instance, in a debate with a scholar from Damascus, who had requested to debate with the Imam’s (a) students, the Imam (a) asked Hisham b. Salim to have a debate with him on theology. On another occasion, the Imam (a) told a person who wanted to debate with him to debate with his students first. The man debated with Humran b. A’yan about the Quran, with Aban b. Taghlib about Arabic literature, with Zurara about jurisprudence, and with Mu’min al-Taq and Hisham b. Salim about theology and was defeated by all of them.
Ahmad b. Ali al-Tabrisi has collected some of the debates of Imam al-Sadiq (a), some of which are the following:
From the life of Imam al-Sadiq (a), it can be inferred that he (a) kept himself away from politics and kept this position in both Umayyad and Abbasid times. However, while Imam (a) kept away from political rivalry, he (a) was very attentive to the society and its destiny, and he (a) advised rulers about justice in the government, consultation with people and caring about their requests.
Refraining from Uprising
Despite the weakness of the Umayyads at his time, Imam al-Sadiq (a) stayed away from uprising and political conflicts. According to al-Shahrastani, Abu Muslim al-Khurasani sent a letter to the Imam (a) after the demise of Ibrahim al-Imam, calling him the one who deserves the caliphate most and inviting him to accept the caliphate. However, the Imam (a) wrote to him: “You are not one of my helpers, and the time is not my time.” Abu Salama also wrote a similar letter to the Imam (a), and the Imam (a) burned his letter in response. Imam al-Sadiq (a) did not participate even in the uprising of his uncle Zayd b. ‘Ali. According to a hadith, the Imam (a) mentioned the lack of faithful supporters as the reason why he refused to revolt.
Disagreement with ‘Abd Allah al-Mahd
Toward the end of the rule of Umayyads, some of Banu Hashim including ‘Abd Allah al-Mahd and his sons and also al-Saffah and al-Mansur gathered in Abwa’ to pledge allegiance to a person among themselves. In that session, ‘Abd Allah introduced his son as “al-Mahdi” and asked others to give allegiance to him. When Imam al-Sadiq (a) was informed about their intention, told ‘Abd Allah, ‘If you think your son is al-Mahdi, [you are wrong] he is not al-Mahdi, and it is not the time for the coming of al-Mahdi (a) yet.” ‘Abd Allah became angry and accused him of envy. Imam al-Sadiq (a) swore that his words were not out of envy and foretold that the rule will be for al-Saffah and al-Mansur and ‘Abd Allah and his sons will be killed.
Relationship with the Caliphs
Although Imam al-Sadiq (a) refused to revolt against the caliphs of his time, he did not have a good relationship with them. On one occasion, when the Imam (a) was on pilgrimage, he proclaimed Ahl al-Bayt (a) as God’s chosen servants and mentioned the hostility of the caliph Hisham b. Abd al-Malik towards Ahl al-Bayt (a). In response to the Abbasid caliph al-Mansur al-Dawaniqi, who had asked Imam al-Sadiq (a) to visit him as other people do, the Imam (a) wrote, “We do not have something to fear you for, you do not have anything of the hereafter for which we should have hopes in you, you are not in a blessing to congratulate you for, and you do not think that you are in affliction to send you our condolences. So why should we be around you?!”
Burning the House of Imam al-Sadiq (a) According to a report, when al-Hasan b. Zayd was the governor of Mecca and Medina, he set fire to the house of Imam Sadiq (a). In the fire, the door and the corridor of the house burned. The Imam (a) came out of the house crossing the fire saying, “I am the son of the Roots of the Earth [i.e., Isma’il (a)]; I am the son of Ibrahim, God’s Friend.”
Except the third decade of the second century (fifth decade of the eighth century CE), which coincided with the fall of the Umayyad caliphate, both the Umayyad and Abbasid caliphs kept the activities of the Imam (a) under watch. Political pressure on the Imam (a) reached its peak towards the end of the Imam’s (a) life. According to some reports, al-Mansur’s agents would persecute those Shiites who were in touch with the Imam (a) and even execute them. Because of these persecutions, the Imam (a) and his companions had to use taqiyya. 
According to a report, when Sufyan al-Thawri visited him, Imam al-Sadiq (a) advised him to leave because they were under watch. According to a hadith, the Imam (a) told Aban b. Taghlib to respond to people’s jurisprudential questions by giving them the opinions of Sunni scholars in order not to be persecuted. Also, several hadiths have been transmitted from Imam al-Sadiq (a) which emphasize the importance of taqiyya, according to some of which taqiyya is equal to prayer.
There are many reports about the moral characteristics of Imam al-Sadiq (a), including his asceticism, generosity, abundant worship, and recitation of the Quran. Malik b. Anas, the head of the Maliki school of jurisprudence reports that during the time he used to visit Imam al-Sadiq (a), the Imam (a) was always in one of the three states: praying, fasting, or saying dhikr.
It is reported that the Imam (a) gave four hundred dirhams to a beggar, and when he thanked the Imam (a), he (a) gave him his ring which was worth 10,000 dirhams. According to another report, the Imam would put some bread, meat, and money in a bag and would take it to the houses of the poor and divide it among them, without letting them know who he was. Abu Ja’far al-Khath’ami reports that Imam al-Sadiq (a) gave him a bag of money and asked him to give it to someone from Banu Hashim without telling him from where the money was coming. When Abu Ja’far gave the money to that man, he prayed for the sender and told him that this person always sends him money, but Imam al-Sadiq (a) never sends him anything even though he is rich!
During the reign of al-Saffah and al-Mansur, Imam al-Sadiq (a) was summoned to Baghdad several times. In these travels, the Imam (a) also visited Karbala, Najaf, Kufa, and Hira. According to a report by Muhammad b. Ma’ruf al-Hilali, when the Imam (a) visited Hira, a great number of people went to see him such that he could not get the chance to visit the Imam for several days.
The Imam’s (a) mihrab in the Mosque of Kufa, located on the eastern side of the mosque near the grave of Muslim b. Aqil, and also his mihrab in al-Sahla Mosque are among his memorials in Iraq. Imam al-Sadiq (a) also visited the grave of Imam al-Husayn (a) in Karbala. On the banks of the Husayniyya river in Karbala, there is a building, inside which is a memorial mihrab for Imam al-Sadiq (a). 
Revealing the Location of Imam Ali’s (a) Grave
It is reported that Imam al-Sadiq (a) visited the grave of Imam Ali (a) and showed its location, which was previously hidden, to some of his companions. According to al-Kulayni, the Imam took Yazid b. ‘Amr b. Talha to a place between Najaf and Hira and showed him the grave of Imam Ali (a). Al-Shaykh al-Tusi also reports that Imam al-Sadiq (a) visited Imam Ali’s (a) grave and prayed beside it and told Yunus b. Zabyan that it was the grave of Amir al-Mu’minin (a).
In his Rijal, al-Shaykh al-Tusi have mentioned the name of 3200 people as the transmitters of hadiths from Imam al-Sadiq (a). Al-Shaykh al-Mufid in al-Irshad extended the count of his transmitters to 4000. It is said that Ibn ‘Uqda, have mentioned names of 4000 transmitters in a book about the students of Imam al-Sadiq (a).
Some of the most famous students of Imam al-Sadiq (a) are:
Some of his companions were expert in specific fields. Humran b. A’yan was expert in Qur’anic sciences, Aban b. Taghlib in Arabic literature, Zurara b. A’yan in fiqh, Mu’min al-Taq and Hisham b. Salim were expert in theology. Other students of Imam al-Sadiq (a) who were experts in theology are Humran b. A’yan, Qays al-Masir, and Hisham b. al-Hakam.
Some of the important Sunni scholars were among the students of Imam al-Sadiq (a). According to al-Shaykh al-Saduq, Malik b. Anas said that he used to go to Imam al-Sadiq (a) and listen to the hadiths that the Imam (a) quoted. In his al-Muwatta’, Malik has quoted some hadiths on the authority of Imam al-Sadiq (a).
Ibn Hajar al-Haytami says that Sunni scholars such as Yahya b. Sa’id, Ibn Jurayh, Malik b. Anas, Sufyan b. ‘Uyayna, Sufyan al-Thawri, Abu Hanifa, Shu’ba b. al-Hajjaj, and Ayyub al-Sakhtiyani have narrated from Imam al-Sadiq (a).
Some of the well-known hadiths of Imam al-Sadiq (a) are as follows:
In some sources, a number of letters and treatises are attributed to Imam al-Sadiq (a). The authenticity of some of these works cannot be verified, but some of them are reported in sources such as al-Kafi and therefore can be regarded as authentic with high probability. The following are among these works:
There are also collections of sayings attributed to the Imam (a) and reportedly compiled by his students, some of the published ones are:
Imam al-Sadiq (a) has had a high place in the eyes of Sunni scholars. Abu Hanifa, one of the prominent Sunni leaders, considered the Imam as the most knowledgeable Muslim and the greatest jurist among them. According to Ibn Abi l-Hadid, great Sunni scholars such as Abu Hanifa, Ahmad b. Hanbal, and al-Shafi’i were directly or indirectly the students of Imam al-Sadiq (a).
However, in Sunni jurisprudence, the viewpoints of Imam al-Sadiq (a) have not been given their due importance, and Shiite scholars such as al-Sharif al-Murtada criticized Sunni scholars for this. 
There is a disagreement about the day and the month of the martyrdom of Imam al-Sadiq (a). The famous viewpoint of earlier Shia scholars is that it was in Shawwal, but the day is not mentioned in earlier sources. However, later sources considered Shawwal 25 (December 14, 765) as the day of his martyrdom. In contrast to the famous viewpoint, it is quoted form Misbah al-Kaf’ami in Bihar al-Anwar that Imam al-Sadiq (a) was martyred in Rajab 15, but this report is not found in Misbah al-Kaf’ami. 
Al-Shaykh al-Saduq clearly states that the Imam (a) was poisoned by al-Mansur al-Dawaniqi and passed away as a result. Ibn Shahrashub in his al-Manaqib, al-Tabari al-Saghir in Dala’il al-imama and al-Sayyid b. Tawus in his Iqbal also expressed the same statement. Yet al-Shaykh al-Mufid held that ther there is no decisive reason how he was martyred.
Many hadiths indicate that Imam al-Sadiq (a) introduced Imam al-Kazim (a) as his successor and the executor of his will to his close companions several times. However, because of the persecutions of the Abbasids and to protect the life of Imam al-Kazim (a), the Imam (a) mentioned five people in his will, including the Abbasid caliph, as its executors.
As a result, even some of the prominent companions of the Imam (a) became hesitant for a short time about who his successor was. Some of them first went to ‘Abd Allah al-Aftah and asked him questions, but his answers did not convince them. Afterward, they met Imam al-Kazim (a) and were satisfied by his answers implying that he was the true successor of Imam al-Sadiq (a).
Schism among the Shi’a
After the martyrdom of Imam al-Sadiq (a), a number of sects emerged among the Shi’a. One group denied the death of Isma’il, the son of Imam al-Sadiq (a), and regarded him as the Imam after his father. A number of people in this group, who gave up the belief that Isma’il was alive, maintained that his son Muhammad was the Imam. This group was later called the Ismailiyya. Another group believed in the imamate of Abd Allah al-Aftah and were called Fatahiyya, but when Abd Allah passed away in just seventy days after his father, they accepted the imamate of Imam al-Kazim (a). Another group, following a person called Nawus, did not accept any other Imams after Imam al-Sadiq (a) and were known as the Nawusiyya. Another group believed in the Imamate of Muhammad al-Dibaj. 
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