Abu Hanifah the leader of the Hanafi school of thought, said:

"I did not find anybody more knowledgeable in jurisprudence than

Ja"far-ibn-Muhammad.

 Once" Mansoor (the Abbassid ruler) told me: people are very attached to Ja"far ibn-Muhammad. I ask of you to prepare religious questions so difficult that he will not be able to answer. After I prepared the questions, Mansoor al - Abbassi called me to his court. When I entered, I saw Ja"far ibn-Muhammad sitting next to Mansoor. I started to ask the forty questions which I had prepared. In response to each question, he (Imam Ja"far Sadiq) expressed the views of each school of thought of Islam and then the view of the Shi"ite sect. Sometimes the Shi"ite view was the same as the others and sometimes it differed. Ja"far ibn Muhammad replied to all forty questions in the same manner."

Then abu-Hanifeh goes on to say: "Didn"t we (Muslims) believe that the most knowledgeable of us is the one who is well acquainted and well informed of the different views of the people"(Tazkerat-al-Hufaz Vol.1 p.1 57)

Malik ibn Anas, the leader of the Maliki school of thought said: "Several times I had the Opportunity to meet Ja"far ibn Muhammad. Whenever I saw him he was either praying or reciting the Holy Qur"an or fasting. He was among those pious scholars who feared God." (The Book of Malik, written by Abu-Zuhrah P.28)

"No eyes have ever seen, no ears have ever heard, and no heart has ever found anybody greater than Ja"far ibn Muhammad Sadiq in knowledge, piety, and worship."

Ibn Hajar Asghalani, the distinguished Islamic historian, said:"Ja"far ibn Munammad ibn Ali ibn Hussain ibn Ali ibn Abi Talib is the most honest among Jurisprudents." (Taghrib-al-Tahzib p.68)

Abu Nu"aim Isfahani, the renowned Islamic historian, said:
"Ja"far ibn Muhammad is the righteous Imam and the one who has inherited the Imamate and the leadership."(Helyat-ul-Ulya Vol.3 P.192)

Ibn Khallakan, the famous Islamic historian and biographer, said:"Ja"far, the son of Muhammad Baqir, is one of the twelve Imams of the Shi"ites.

He was among prominent personalities of the Ahl- al-Bait. He was named "the honest" for his honesty and was well-known among the people."(Wafiat-ul-A"yan)

Abu al-Fath Muhammad ibn Abdul-Karim Shahrestani, the Islamic historian, said

:"Ja"far-ibn-Muhammad al-Sadiq is enormously knowledgeable. He has no desire for worldly matters and is a very pious man. He resided in Medina for a while and taught his followers the secrets of the holy religion of Islam. Then he entered Iraq and lived there for some time. He never fought with anybody for "Khilafa" (leadership). Yes, whoever is deeply surrounded by the ocean of knowledge will never sink in a small river. And whoever climbs the mountain of the truth will not be afraid of falling down." (Mellal wa Nehal Vol.1 p272)

Mansoor Dawanighi, the Abbasside Khalif, said:"Ja"far is among those selected by God and a leader in charitable deeds. There is no Ahl-ul-Bait unless there is a narrator among them and today's narrator is Jafar-ibn-Muhammad."(Tarikh Ya"kubi Vol.3 p. 177)

 Ibn-Abi al "awja", the renowned narrator said:
"He is above human beings. If there is one person in the world who can be deeply obsessed with spiritual matters and then come out of that state, anytime he wishes, it is Jafar-ibn-Muhammad."(Al-Imam Sadiq Walmathahib al-Araba"a Vol.1 p.54)

Ibn al Jawzi, Abdul-Rahman, the religious historian, said: "Worshipping and praising God had kept Jafar ibn Muhammad from seeking the position of leadership" (Safwat-ul Safwat Vol2 p94)

Kamaluddin Muhammad ibn-Talha Shafi"i, the leader of the Shafi"i School of thought, said:
"Jafar- ibn-Muhammad is among the "sadat" and jurisprudents of the Ahl-ul-Bait. He is a perpetual worshipper and reciter of the Holy Quran and perceives the profound meanings of the Book."

"His face reminds one of the Hereafter, his words teaches one piety in this world, and following his commands would take one to the heaven. The light in his face depicts his kinship to the Prophet and honesty in his deeds attests to his relationship to the Prophet's household."

ammaluddin Abulmahasen, the eminent religious historian, said:"Jafar Sadiq, the son of Muhammad Baqir, is the Imam, "Sayyid", Abu-Abdullah, Hashemi, Alawi, and Hussaini. He was called "the patient" "the learned", and "the pure" but by most people he was known as: The honest"." (Al Nujum-al-Zahira Vol.2 p.8)

Alusi, the Mufti of Baghdad, said:"Abu Hanifah, the leader of the Hanafi school of thought, has clearly stated that: Nu"man (Abu-Hanifah) Would have been lost in this world if he had not benefited from the great knowledge of Jafar Sadiq in the two years of his apprenticeship.(Tuhfah Ethna-Asharia p.8)

Dr. Ahmad Amin the late historian and author of Fajr ul-Islam, said:

"Imam Jafar Sadiq was the most prominent religious personality of the Shi"ite sect at that time and perhaps in all era. In one word, Imam Ja"far is among the greatest personatities in his time and afterwards. (AI-Imam Sadiq written by Assad Haydari, Vol.1 p.62)

Imam Sadiq (A.S.) Said:

Who is the faithful?

The faithful is the one: who earns "halal" income, who has good virtues and a pure heart, who donates his extra income for charitable deeds, who refrains from idle-talking, who does no harm to people and who treats all justly.

Source: Tebyan