Ja’far ibn Muhammad (AS) known as the Ja’far as-Sadiq (AS) is the sixth Shiite Imam. Imam Sadiq (AS) was born on 17 Rabi al-Avval 83th (702 CE) in Medina. His father, the previous Imam, was named Muhammad al-Baqir (AS) and his mother was called Umi-Farvah. After his father, Imam Sadiq (AS) became the Imam of the Shias and his leadership lasted for about 34 years. The era of Imam Sadiq (AS) was the time of instability and wars, since the Umayyad dynasty were weakened so much due to the battles they had in the Islamic territory. In addition , Abbasid dynasty were trying to topple the Umayyad government and reign over the whole Islamic world. The weakness of the rulers gave Imam Baqir (AS) and Imam Sadiq (AS) a perfect opportunity to spread the teachings of Shiism and train so many Shia scholars. At last, Imam Sadiq (AS) was martyred by the order of the Mansur (an Abbasid Caliph) on 148 H (765 CE). 

What does “Sadiq” mean?

The word “Sadiq” means an honest person who does not tell lies. 
Once, Imam Sajjad (AS), the grandfather of Imam Sadiq (AS) was asked: “Who is the Imam after you?”
“My son Muhammad (AS) who opens knowledge and after him his son Jafar who is called in the skies as ‘Sadiq’” Imam Sajjad (AS) replied. 
He was asked once more: “Why out of you all, he is called “Sadiq” while you all are honest?”
Imam Sajjad (AS) said: “Because the Prophet (PBUH & HP) said: ‘Name my son Jafar ibn Muhammd as “Sadiq” because there will be another Jafar in the future who falsely claims to be an Imam and he is named “liar” by Allah’” (On the contrary, Jafar ibn Muhammad is honest because he is a true Imam). (1)
The liar Jafar mentioned in the hadith is the son of Imam Hadi (AS), the eleventh Imam. 

The knowledge of Imam Sadiq (AS)

All Shiite Imams were known for their abundant knowledge in their time; but among all, Imam Baqir (AS) and Imam Sadiq (AS) were different. Due to the fact that Umayyad dynasty were weak and unstable in those times, Imam Baqir (AS) and Imam Sadiq (AS) had this chance to unveil the abundant knowledge of the Prophet’s household. 
About 4000 people learned from Imam Sadiq (AS) and narrated hadiths from him . (2)
Amr ibn Abi al-Mighdam, a Sunni scholar, says: 
“Every time I looked at the face of Jafar ibn Muhammad (AS), it would make me sure that he is a descendant of the prophets. Once, I saw him in Jamrah (a place in Mecca where the pilgrims gather) and he was telling people: ‘Ask me! Ask me!’” (3)
Hassan ibn Ali al-Vasha, a Shiite hadith narrator, says:
I saw about 900 sheikhs who all would narrate hadiths from Jafar ibn Muhammad (AS) (4).
Once Abu Hanifah, one of the most knowledgeable and popular Imams of the Sunnis, was asked: “Who do you think is the most knowledgeable person in religious fields?” he said: “I do not know anyone more knowledgeable than Jafar ibn Muhammad (AS)” (5).
Imam Sadiq (AS) is mostly known for his knowledge in Islamic laws and because of this, the Shiite school of law is called “Jafari School”. The hadiths narrated from Imam Baqir (AS) and Imam Sadiq (AS) are more than all the hadiths narrated from the Prophet (PBUH & HP) and the other Imams all combined together.

The moral attributes of Imam Sadiq (AS)

In addition to his wisdom and knowledge, Imam Sadiq (AS) was also known for his significant moral qualities. 
Muhammad ibn Talha says: 
“Imam Sadiq (AS) was the greatest person among the Prophet’s household and he was so knowledgeable and he would pray and recite the Quran so much and he was an ascetic person.” (6)
Malik ibn Anass, one of the Sunni school’s head, says: 
Every time I met him, he was in one of these three moods: either praying, fasting or whispering prayers (7).
Hisham ibn Salim, a famous apprentice of Imam Sadiq (AS) says:
Abu-Abdillah (Imam Sadiq (AS)) would always take a bag full of bread, meat and money in the darkness of the nights and go to the house of the needy ones in Medina and give it to them while they didn’t know him. Then, when he died, the people weren’t given those goods anymore and from that, they found out about his identity. (8)

Resources 

1.  Al-Khara’ij, ar-Ravandi, vol.1, pg.268
2.   Al-Irshad, Sheikh Mufid, vol.2, pg.179
3.    Siar A’lam an-Nubalah, Zahabi, vol.6, pg.257
4.    Rijal al-Kashi, vol.1, pg.138-139
5.   Siar A’lam an-Nubalah, Zahabi, vol.6, pg.257
6.    Kash al-Qummah, Irbeli, vol.2, pg.691
7.  Bihar al-Anvar, Majlesi, vol.47, pg.16
8.   Kafi, Koleini, vol.4, pg.8
    

At times of hardships over which we have no power, sometimes we find no remedy other than turning our face toward our Creator, the One who is aware of the manifest and the hidden. For sure, not everyone is able to endure difficulties and keep his/her faith; we might break easily and lose our hopes. However, those whose heart is dedicated to a Higher power and trust in His will find peace and hope in every difficult moment of their lives. Imam Sajjad (AS) is the perfect example of such people. His sincere worship to Allah at times when he was most distressed and under pressure, not only gave him the strength to deal with the problems but also left a legacy for generations after him to learn how to survive through putting trust in Allah. 

In what follows, we will learn more about the life of this significant Muslim figure and a descendant of Prophet Muhammad (PBUH&HP).

Birth and Lineage 

Ali ibn al-Hussain ibn Ali ibn Abi Talib (AS), known as Imam Sajjad (AS) and Imam Zayn al-Abidin (AS), is the son of Imam Hussain (AS) and Shahrbanu, the daughter of Yazdgerd, king of Persia [1]. He is the fourth Imam of Shias. He was born on January 6, 659 A.D in Medina. He had many children, the most famous among whom was Muhammad al-Baqir (AS), the fifth Imam of Shias. 

Imam Sajjad (AS) in the Battle of Karbala 

After being invited by Kufa people to help them rise against their tyrant ruler, Imam Hussain (AS) and his family, including Imam Sajjad (AS), set on a journey from Mecca toward Kufa, today's Iraq. On their way, Imam Sajjad (AS) was inflicted with high fever and became severely ill. His illness became even worse on the day of the battle of Karbala, to which Imam Hussain (AS) was forced, and couldn't even stand on his feet. 

However, he constantly got the news of the events on the battlefield from his aunt, Lady Zaynab (AS), and others. When all of Imam Hussain's (AS) companion got martyred, he tried to guide Yazid's army one last time and called out: "Is there anyone who would defend Prophet Muhammad's (PBUH&HP) progeny? Is there anyone who would worship the one and only Allah, who would fear Him and be on our side? And is there anyone who would help us for the sake of Allah?" On hearing this touching words of his father, Imam Sajjad (AS) got up from his sickbed with all his remaining strength, hold out to his walking stick, and started for the battlefield to help his father despite his severe condition. However, when Imam Hussain (AS) saw him, urged Lady Zainab (AS) to take him back to the tents so that he wouldn't get martyred like others and preserve the legacy of Prophet Muhammad's (PBUH&HP) progeny. 

After Imam Hussain's (AS) martyrdom, Imam Sajjad (AS) along with lady Zaynab (AS) and other children and women from Imam Hussain's (AS) camp were treated utterly disrespectfully by Yazid's army and taken as captives. It's been said that since Imam Sajjad (AS) was ill and unable to sit on the camel, he was tied to it while in the chain. They were then transferred to Kufa. 

When they reached Kufa, to belittle them more, Yazid's soldier took them right in the middle of the town and in front of people to witness their pitiful condition. However, Imam Sajjad (AS), despite his bodily weakness, found it the best chance to talk to people and inform them of what had befallen on them. He then stood in front of people and invited them to silence. First, he praised Allah and His Prophet (PBUH&HP). And then gave this moving speech: 

"O' people! For the ones who don't know me, I should say that I am Ali, son of Hussain (AS), who was martyred beside the Euphrates, without being guilty of any crime from which he would be taken revenge, I am the son of the one who has been dishonored, whose property has been plundered and whose wife and children were taken as captives, I am the son of the one who has been killed painfully, yet we are honored and proud. O' people! Do you remember the letters you have sent to my father and deceived him, then took an oath of allegiance with him, yet went into war with him and left him alone? Woe to you! What have you stored [for your afterlife]! How would you face Prophet Muhammad (PBUH&HP) when he enquires: "Did you kill my progeny and dishonor me? Aren't you my Ummah (followers)?" [2] 

People were ashamed and wanted to make promises to Imam Sajjad (AS), yet he didn't accept their oaths. Then, they were taken to Ubayd Allah b. Ziyad's [i] palace. He first meant to kill Imam Sajjad (AS); however, with lady Zainab's (AS) strives, he changed his mind. After some days, by order of Ibn Ziyad, they were transferred to Damascus. They had a tough time in this city and were kept in the ruins of Damascus. Once, they attended Yazid's palace, where Imam Sajjad (AS) gave another persuasive speech in defense of Prophet Muhammad's (PBUH&HP) progeny. He introduced himself, his father, and his grandfather to people and told the people of Damascus that what Yazid and his agents have propagated are not valid. His father was not a rebel and did not want to disturb the Muslim community and make mischief in Islamic lands. He rose for truth and by invitation of Muslims to remove heresies brought up in religion and bring the simplicity and purity it had at the time of his grandfather. This speech proved the rightfulness of Imam Hussain (AS) and his movement at the face of Yazid's corrupt rule [3]. 

Imam Sajjad (AS)'s  Leadership

The leadership of Imam al-Sajjad (AS) began after the martyrdom of Imam Hussain (AS) on the day of Ashura and lasted for 34 or 35 years. During this time, the Islamic society, as the result of the corrupt governing system, was full of injustices and went totally against the teachings of Prophet Muhammad (PBUH&HP). 

Being fully aware of the dire social and political conditions of the society, Imam Sajjad (AS) knew very well that he couldn't overtly invite people toward truthfulness and rise against the false strategies of the ruling government. Therefore, he chose to follow a wise and discreet policy in fighting against the oppression in society. Also, he meant to preserve the invaluable legacy left to him by his fathers and pass it safely to the following generations. 

To this purpose, he made perfect use of indirect ways of teaching people and informing them of the vices which prevailed in the society. Praying was one of these strategies. Through his famous prayers to which we have access in Al-Sahifa al-Sajjadiyya, he not only taught people about how to connect with Allah and trust Him in helping them to overcome their problems but also posed his opposition against the present situation. 

Moreover, despite severe pressures of the government of the time, Imam Sajjad (AS) managed to train some Islamic scholars to whom he transferred the knowledge he inherited from his fathers and the words and deeds of his great grandfather, Prophet Muhammad (PBUH&HP) and his true teachings. 

Imam Sajjad (AS)'s Prominent Characteristics

An Ardent Worshipper 

As his name suggests, Imam Sajjad (AS) was one of the most ardent worshippers of Allah after Prophet Muhammad (PBUH&HP). He used to pray thousands of Rak'as of Salat in a matter of a day, which made him prostrate very much; thus, he is called Sajjad, meaning the person who prostrates much [4]. His prayers and supplications recorded in Al-Sahifa al-Sajjadiyya were sincere and straightforward, which made them even more touching and impressive. Through these prayers, he revealed the perfect manner of calling out to Allah and finding our way to Him in every breath and whatever difficulty we are dealing with. Also, he used his prayers to covertly show his opposition against the tyrants of his time and make people aware of the situation.

Generous, Kind and Compassionate

Imam Sajjad (AS) following his father, Imam Hussain (AS), grandfather, Imam Ali (AS), and great grandfather, Prophet Muhammad (PBUH&HP), was fully observant of his manner toward people and treated them with his unbound compassion and generosity. Many accounts narrate this singular attitude of Imam Sajjad (AS) in his social and personal life. 

For instance, once he was riding on his horse when he saw a group of lepers who were eating breakfast. When they saw Imam Sajjad (AS), they invited him to join them. Imam Sajjad (AS) said: "I would be glad to eat with you if I weren't fasting." As soon as he reached his house, he ordered his servants to cook some good food of the best things they had. Then he invited all those lepers to his house and joined them to eat dinner together [5]. 

In another account, it's been said that he used to fast during the day and cooked food himself while fasting. Then he would divide all the food among people and break his fast with some bread and dates [6]. 

His forgiving and humble character is recounted in many narrations, which reveals him to be the best role model for all humankind. In one instance, one of Imam Sajjad's (AS) adversaries insulted and cursed Imam in front of other people. Imam's servants came to punish the one who offended him, yet Imam ordered them to leave him alone, saying, "there is something more behind his manner toward us." Then he addressed the man and said, "Is there anything you need?" the man felt ashamed and didn't answer. Imam gave his own clothes to him and ordered to provide him with a hundred Dirhams. The man feeling regretful called out, "I witness that you are the son of Prophet Muhammad (PBUH&HP)."[7] The same thing happened again with one of Imam Sajjad's (AS) relatives who met Imam and insulted him. Imam (AS) didn't answer him at the time. Then he went to his relative's house and while the man was expecting to get an angry response from Imam (AS), heard him saying, "My dear brother, a few minutes ago you stood in front of me and told whatever you wanted. Now, if what you said about me is true, then I seek pardon from Allah and ask for His forgiveness, and if what you said is not true about me, then I pray for you to be forgiven by Allah." The man became utterly ashamed and expressed his regret for accusing Imam Sajjad (AS) falsely [8]. 

He was also very famous for his secret charities to the people in need, many of whom found out about this unknown helper just after his martyrdom. He used to put a bag full of bread on his back and carry it to give out to the poor at night. It is narrated that he would gather whatever food remained in his own house, covered his face, and gave them all to the destitute of Medina [9]. 

Knowledgeable and Wise

Imam Sajjad (AS) was one of the most knowledgeable and learned personalities of his time. Muhammad ibn Muslim al-Zuhri, one of the Islamic scholars, said about him, "I found no Hashemite [ii] greater or more knowledgeable than him in fiqh [iii]."[10] He was an expert in all the matters of his time and had access to the sciences, which wasn't available to the majority of people. 

Notable Books by Imam Sajjad (AS)

The legacy of Imam Sajjad (AS) had preserved through the centuries by the books compiled by the Islamic scholars from his supplications and prayers. The two most well-known of these books are Al-Sahifa al-Sajjadiyya and Risalat al-huquq (Treatise on Rights).

Al-Sahifa al-Sajjadiyya is the collection of Imam Sajjad's (AS) supplications, which also reflects the social status at that time, especially in Medina. The supplications present "his aversion to bad behaviors and speech of people at that time, taking refuge to God from what he saw and heard and clarifying the right path under the guidance of religion and the Quran and purification of souls from pollutions"[11]. This book has been translated into several languages.

Risalat al-huquq is the title of a lengthy narration from Imam Sajjad (AS) compiled as a book. "This narration, which contains over 50 duties of any individual toward others, is, in fact, a treatise on moral conduct in both personal and social life. The rights discussed in this treatise address various social relations of any individual, like the duties toward parents, spouse, children, neighbors, teachers, students, believers, the leader of Congregational Prayer, the government, etc. Because of the particular position and the comprehensive content, several translations and commentaries have been written on this treatise" [11]. 

His Martyrdom 

Imam Sajjad (AS) was martyred in 713 or 714 A.D. with a poison given by order of al-Walid b. 'Abd al-Malik [12]. He (AS) was buried in al-Baqi cemetery in Medina beside his uncle, Imam Hasan al-Mujtaba (AS) [13].

Finally, looking at the fruitful life of Imam Sajjad (AS), one can find the perfect path toward pure humanity. The path offered to us by Allah, which, despite having its own challenges, leads us to the fullest and most meaningful experience of this short life. The leaders are our guiding lights that shine through the darkness of our confusions and fluctuations, show us the way to prosperity, and grant us the opportunity to find Allah in every moment of our lives. 

Notes:

[i] The famous Umayyad commander, the governor of Kufa at the time of the Tragedy of 'Ashura and one of the key persons in the martyrdom of Imam al-Husayn (a) and his companions.
[ii] A famous clan in Medina from which Prophet Muhammad (PBUH&HP) and his progeny are descended. 
[iii] An Islamic science through which practical laws and religious duties of a person in his life are studied.

References:

1. Al-Shaykh al-Saduq, 'Uyun akhbar al-Rida, vol. 2 p. 128.
2. imam Sajjad (AS)
3. Shadidi, Sayyid Ja'far. Zindigani 'Ali b. al-Husayn. p.75.
4. Dhahabi, Muhammad b. Ahmad al-. Al-'Ibar fi khabar, vol. 1, p. 83.
5. Muhammad ibn Ya'qub al-Kulayni, Kitab al-Kafi, vol.2, p.123.
6. Ahmad b. Muhammad b. Khalid al-Barqi, Al-Mahasin, vol.2, p.396. 
7.  Ibn Shahr Ashub, Manaqib Al Abi Talib, vol.3, p.296. 
8.  Al-Shaykh Al-Mufid, Kitab al-Irshad, vol.2, p.145. 
9. Ibn Shahr Ashub, Manaqib Al Abi Talib, vol.3, p.292-3. 
10.  Dhahabi, Muhammad al-. Tadhkirat l-huffaz, vol. 1, p.75.
11. imam Sajjad
12. Mas'udi, 'Ali b. Husayn al-. Muruj al-dhahab wa ma'adin al-jawhar, vol. 3, p. 160. 
13.  Al-Shaykh Al-Mufid, Kitab al-Irshad, vol.3, p.160.